Hello, everyone. Good evening. People attending online, I hope I am audible to you and people who are watching it on YouTube. I hope I'm also audible to you. I'm audible to you also. All right. So we'll start with the session. A short introduction. I'm Sucharitan, Faculty for Science and Technology in Shankara A.S. Academy. So welcome to the free session provided by Shankara A.S. Academy, wherein the main aim of this session is to cover at least 300 questions, sorry, 200 questions and cover 100 themes in various subjects. Wherein today we are going to discuss about science and technology. Before we start the session, I'll give you a general outlay of the session. I've taken 30 questions. So these 30 questions, they've taken from different fields of science and technology, like space science, astrophysics, biotech, nuclear science, electronics, communication, information technology, nanotechnology, and then from basics of NCRT. Basically, at least two or three questions will be there in all these fields. Now, how we are going to approach the session is, first, I will show you the question and then generally, you know, assume you're going to write your prelims examination. It's 120 minutes, wherein you have to attend somewhere around 100 questions. So I have assumed or I have assigned somewhere around 50 seconds for each of the questions. So once I show you the question, so Bar will run at the top of the screen, wherein before it runs out, which will be in 50 seconds, please make sure you drop your answers. So all the answers that will be given as input through the Zoom meeting, I will take it as the answers and then based on that, we'll proceed with the discussion. This is the idea here. So we'll start with the first question. Yeah, please wait a minute. We're starting the first question in space science. I will display the question. Online people, I'm watching your messages on the Zoom. You can drop your messages here. The question on your screen now. So please zoom to the board. Okay. Do you want the board to be zoomed in? Is it not clear to you? Do you want the board to be zoomed in? I don't know. Is it fine now? People are attending on the Zoom. Yeah. I hope the Zoom level is optimum now. Okay. So based on the answers you have given, first one, you can launch a satellite up to 8,000 kilograms to the lower orbit. It is correct. So first of all, you have to understand what is the lower orbit. Let's say if this is the surface of earth and if a satellite is placed up to 2,000 kilometer from the surface of earth, then you call it as a lower orbit. So it can be anywhere starting from generally 180 kilometer or up to 2,000 kilometer. You call it as a lower orbit wherein of all the launch vehicles that India has right now, the GSLV Mark III, which is the heaviest launch vehicle of India. This is capable of carrying up to 8,000 kilograms to the lower orbit. If you take the payload capacity of GSLV Mark III to the lower orbit, that is less than 2,000 kilometer, it can carry up to 8,000 kilogram of payload. This can be anything, a satellite, a spacecraft, or even astronauts, or anything that can be up to 8,000 kilogram can be carried by GSLV Mark III to the lower orbit, that is up to 2,000 kilometer. Then when we talk about GTO, that is geostationary transfer orbit, where the satellite should be placed in a temporary orbit and then it will be lifted to a very high earth orbit, somewhere up to 35,000 kilometer. So for such orbits, this GSLV Mark III can carry up to 4,000 kilogram. Or in very simple terms, if you want to launch a communication satellite which is much heavier, which has to be placed in a very high earth orbit, India can send up to 4,000 kilogram. When if you want to place any other imaging satellite or any other minor satellites which are placed at the low altitude, India can send up to 8,000 kilogram. So these are the launch capacities of GSLV Mark III. Based on this, first statement is correct. Second statement. India sells sufficient in the production of liquid and cryogenic engines. This statement is also correct because the liquid engines developed by India, these are called as Vikas engines. First they were integrated in PSLV, the Polar Satellite Launch Vehicle. So India sells sufficient in liquid engine. You would have seen movies like the Rocket Renumbia Effect and everything that discusses about Vikas engines. Now coming to the cryogenic engines, right now India has two cryogenic engines. First one is CE 7.5. This is the first indigenous cryogenic engine developed by India. Where in the largest cryogenic engine developed by India, it's called a CE 2.5. Where in CE 7.5, right now, it is operating in GSLV Mark II. Where in CE 2.5, this is operating in GSLV Mark III, which means two types of cryogenic engines are used by India. For both of them, India has self-sufficient capabilities. In other words, we can domestically produce it without any other country's support. Even though these cryogenic engines are inspired by the Russian model, right now India has indigenous capabilities. So the second statement is correct. Third one, GSLV Mark III has the highest success rate among all the launch vehicles of India. This statement is wrong. That's because when we talk about success rate, it's about how many missions you have sent and out of which how many missions were successful. If you take the success rate, GSLV Mark III has lesser success rate. Where in PSLV, that is a Polar Satellite Launch Vehicle, this is considered to be the most reliable launch vehicle of India. That's because in the entire service history and all the commercial missions, so far only two failures. One was in 1993, the other was in 2017, which means this is considered to be the most versatile workhorse or this is considered to be the most reliable launch vehicle of India. Where in the third statement is wrong, based on this answer should be one and two only. And after I tell you the answer, again, I will give you like 15 to 30 seconds reserved for any doubts. Online people, if you have any doubts, you can drop your messages quickly. Many of you have answered B, few of you have answered C. Where in C is wrong answer? I hope you understood. How many failures for Mark III are not required, sir, but when we were trying to send Mangalyan repeatedly, GSLV Mark III was showing failures. And that is why the India's Martian mission or the Mangalyan was sent through PSLV. So from what I've heard, it has very lesser success rate and also more number of failures compared to PSLV. This is sufficient. The numerical data is not required. Which has the highest success rate? PSLV has the highest success rate. PSLV, Polar Satellite Launch Vehicle. PSLV has the highest success rate. We have one more question. Where CE is used? The cryogenic engine 225. By the way, Narendra, CE20, CE25, both are same. CE25 is the name of the program, CE20 is the name of the engine. CE2025 symbolizes the same thing and they are part of GSLV Mark III. What is the height of GTO? It depends on the altitude where you have to place the satellite. If you want to place a satellite at 35,000 km, then the GTO can be up to 7,000 km from where we will be rising it. Suppose if you want to place a navigation satellite somewhere around 10,000 km, then 4,000 km can be GTO. So this GTO depends on the mass of the satellite and also depends on the destination of the satellite. It has a variable range, but definitely higher than a lower part of it. Is it clear? Can we go to the next question? All right. Coming to the second question related to navigation systems. B is the majority of answer. Very few of you have answered C. Many of you have answered E. We will see this question. Navigation system in mobile phones can predict our location by trilateration technique. This is true. That's because if I'm going to turn on GPS here, now my phone is going to receive signals at least from 13 satellites. Since GPS has somewhere around 24 satellites, including the backup satellites, 8 to 13 satellites will send signals to my mobile phone. Now the mobile phone has a GPS receiver, which is going to calculate distance of the satellite from the mobile phone. The distance of the satellites from my mobile phone is calculated. Based on this, your location will be predicted. So this method is called as trilateration. In very simple words, if you're going to electronically calculate sides of a triangle or sides of a shape, then it is called as a trilateration technique. And this should not be confused with triangulation technique. Because triangulation technique, you use the angles of a triangle to determine its length. That is different. Where in navigation systems, they use trilateration techniques. Triangulation is used for land survey methods, wherein this is used in navigation satellites. So the first statement is correct. Trilateration technique is used by the navigation systems to predict your location. Second one. Navig system by India has satellites in geostationary earth orbit as well as geosynchronous orbit. This is also correct. That's because you classify satellites generally placed at a very high altitude in two. First one, you have geostationary and then geosynchronous. So both these satellites have one common characteristic. That is time period of the satellite. Repeat. Time period of the satellite. In other words, time taken by the satellite to complete one orbit. There is a time period of the satellite. So time period of the satellite equals to rotational period of earth, which equals to 23 hours, 56 minutes and four seconds. In other words, approximately you can write 24 hours. Now the earth is going to take 24 hours to complete one rotation. The satellite is also going to take 24 hours to complete one rotation. That is called as a geosynchronous orbit. Something like this. The earth is taking 24 hours and also the satellite is taking 24 hours. Now in this, you have two subclassifications. First one is geosynchronous, which means this condition is met, but this is not generally placed on the equator. In other words, it is a little bit tilted away from the equator. So it covers certain parts of the northern hemisphere and then it covers certain parts of the southern hemisphere or in very simple terms. If you take the equator to be like this, it makes an eight-shaped path or the area covered by geosynchronous orbit. I repeat, geosynchronous orbit, GSO, it will be like an eight-shaped path where in sections of area will be covered. That's because the earth is rotating in a different angle and the satellite is orbiting in a different angle. This is called as geosynchronous, wherein geostationary earth orbit, GEO, it is basically a special case of GSO. I repeat, geostationary earth orbit, it's a special case of geosynchronous orbit. The only difference is it fulfills this condition, but it is placed above the equator. I repeat, this is placed right above the equator. That's called as a geostationary earth orbit satellite. So what is the statement given here? It says NAVIC system, or in other words IRNSS, Indian Regional Navigation Satellite System. It has satellites in geostationary earth orbit, as well as geosynchronous orbit. This is true. That's because India has placed four satellites in geosynchronous orbit and three satellites in geostationary earth orbit. So this has been asked in previous year, the older UPSI prelims also. That's because you have something like this, seven satellites wherein four satellites are in geosynchronous orbit, which makes eight-shaped coverage and then three satellites are in geostationary earth orbit. So that's why if you see here, GEO, three GEO and then four GSO. So the second statement is true. Coming to the third statement, NAVIC SPS signal, which means standard positioning signal, or interoperable with other global navigation satellite system. So here, global navigation satellite system means it has a global coverage. Throughout the world you can use it, starting from Arctic to Antarctic. Everywhere you go, if a navigation signal is going to give you a coverage, if it is going to provide you signal, you call it as a GNSS, Global Navigation Satellite System. We have four global navigation satellite systems, one is GPS owned by USA, and then you have GLONASS owned by Russia, and then you have GALILEO, that is owned by European Union, and then you have Baidu, that is owned by China. So these are global navigation satellite systems. Wherein if you take NAVIC or IRNSS, these are regional navigation satellite systems, or IRNSS. Now, here it says, NAVIC signals are interoperable with other global navigation satellite systems, wherein recent times when they updated the ISROS webpage, we understood this is true. For the GS students who are attending the session, I particularly told you that navigation systems are not interoperable, which means if I have a GPS receiver, that may not operate with GLONASS, that is true. But here, NAVIC and GPS, these two are interoperable, because there are certain bands in C-band L-band that are interoperable, which means if I have a GPS receiver, it can receive signals from GPS, which belongs to USA, and also it can receive signals from IRNSS, which belongs to India. Certain bands are interoperable. So this statement is also correct. This is update with respect to the data given in GS classes. So make sure you update your notes. One, two, three. All the C statements are correct. So answer is D. All the statements are correct. Second question, answer is D. Do you have any doubts in this? Can we go to the next question? Okay, now Raina has a question. Why A-shape is formed? For that you have to understand, they have this rotating from west to east, wherein the satellite is rotating like this, where the equator is here. So what will happen when it is here? This is going to cover this section of the land. When it is there, it is going to cover other section of the land, but the earth would have rotated. So wherein you can search in Google for GSO, because it's very difficult to explain it here since I don't have animation. Just search for geosynchronous orbit and then go to the image search, put a GIF file you will understand, wherein right now you have to imagine it in a three-dimension here. It makes an A-shaped coverage. Set up one more doubt from Karthik wherein he's asking, for location tri-lateration, for land survey you said, no, what is it? Okay, so Karthik I said, if civil engineering graduates are present online, they'll understand it. It's called as triangulation. The method used in land survey, that's called as triangulation technique, wherein angles of a triangle is used to measure the sites. That is triangulation, but navigation uses tri-lateration. Okay, and one more one. So how many regional navigation system India has? So in Nithishar, India has only one regional navigation system. Generally worldwide, we call two regional navigation systems, which are operational right now. One is called as the IRNSS, or NAVIC, which is owned by India. The other one is QZSS, quasi-zernite satellite system, that is owned by Japan. These two are the regional navigation systems that are completely operational now. So does the one like interoperable makes it GNSS, since it looks very vague? No, no, no. See here, what we have given here is, the signals are interoperable with other global navigation satellite systems. We have not specified, it's interoperable with all global navigation systems or something like that. We have given. It is interoperable with other global navigation systems, which could be anything. Clear? Okay. Kindly display trilateration. You don't have to take a screenshot or copy it here. Varanasi will be sending it to your YouTube link. So Varanasi in the description, once the class is over, we'll be updating the PDF. You can download it from there. Okay. Coming to the third question. Here, I've mentioned four important satellite systems of India, and I've mentioned the spectrum, which is being observed by these satellites. First one. Cartosat. It uses visible light. True. This is often called as India's eye in the sky. That's because it creates very clear images. The spectral resolution of Cartosat. It is speculated to be up to 25 centimeter, extremely high zooming capabilities. It is the sharpest civilian remote sensing satellites. I'm using the term sharpest. That's because it's considered to be sharpest in the world, because there was a satellite called, in fact, it is still operating. There is a satellite called World View 3, which is owned by USA, by a company called Maxar, USA-based company called Maxar. This had a resolution of 30 centimeter, but right now the Indian satellite, that is Cartosat, it has imaging resolution of up to 25 centimeter, which means if you take the civilian satellites that are available for imaging capabilities, this has the sharpest image. So the first one is properly matched. Second one, hyperspectral imaging satellite. HYSIS stands for hyperspectral imaging satellite. So wherein HYSIS, it covers two regions. One is the infrared, the other one is the visible. If you are unable to comprehend all these radio spectrums, understand electromagnetic spectrum. It has seven different waves. It starts from radio and covers radio, micro, infrared, visible, UV, X-ray and gamma. And here the general classification, which I tell in the GS class as usually, you draw a line here, wherein these four are generally used for communication purposes. That is, radio is used for communication, microwave, infrared and visible. You've had many questions related to VLC, visible light communication and other, even infrared communication. So these four can be used for communication. Generally, we won't use UV, X-ray and gamma for communication. That's because high energy ultraviolet rays, X-rays and gamma rays, these are ionizing in nature, which means they can knock out electrons from your, from atoms in your body, which can lead to cancers, or on a longer end can even lead to genetic damages. So generally, when we talk about communication, we use these four for communication purposes. Similarly, for imaging purpose also, we can use all of these electromagnetic waves, especially these four electromagnetic waves. Because when you imagine taking a photo, you always imagine a lens that captures light. That is our normal phone camera. In fact, right now our phone cameras are capable of capturing visible as well as infrared. Right now, most of the advanced phone cameras, it uses these two parts of the spectrum, wherein for imaging purpose, we can use all four of them, especially in satellite systems. So here it is given, high CIS uses infrared plus visible light. That is hyperspectral imaging satellite uses infrared plus visible light. That's true. Second one is also properly matched because this can record thermal radiations, which means if there is a forest fire or if some organisms are present under the canopy layer of the forest, all these can be faced using high CIS. Coming to the next one, RESAT. RESAT stands for radar imaging satellite. Very important that's because this is India's all-weather satellite system. This is India's all-weather satellite system. All-weather satellite system means day, night, cloudy weather, rainy weather, respective of the weather condition. This can make clear images. So how this particular satellite is capable of making images means it uses microwave basically. It is not going to collect microwave, but instead the satellite is going to beam a microwave that is going to be reflected from the land and using that it creates a simulated image. In fact, the type of satellites are called as or the type of radar used here, it's called as Synthetic Aperture Radar, S-A-R. You can link it with the recent project NISAR, NASA's Synthetic Aperture Radar basically. The NISAR also is going to perform the same function. It's going to take complete picture of the Earth periodically. So similar to that here, RESAT, radar imaging satellite, it's going to take clear pictures by sending microwaves and receiving them back from the land. Based on this, this statement is also correct. RESAT uses microwaves. Even though it's called as radar imaging satellite, which generally symbolizes radio waves, here it uses microwaves. Third one is correct. Fourth one is resource satellite, which is used for resource monitoring purpose. This also uses infrared and visible light. So basically all the four are correctly matched. Answer is D, all the pairs are correctly matched. Answer is D, all the pairs are correctly matched. Do you have any doubts on this? So where can we get this info? Okay, so generally I took it from the Astros webpage itself. So if you go to Astros webpage, it has option called the satellites of India, wherein they have divided into communication satellites, the Earth observation satellites, and then student satellites, small satellites, special scientific missions. So wherein I have covered most of them in this particular session also. So wherein these info are taken from Astros webpage. Then you go to the next one. So what's mean by Nisar? Karthik has a question. So Karthik Nisar means NASA, Astros, Synthetic Aperture Radar, I repeat. Nisar means NASA Astros, Synthetic Aperture Radar. So NASA is building a payload, a particular bandwidth, and Astros is building one more Synthetic Aperture Radar. So both these space agencies together, they're going to put a satellite that will have two different Synthetic Aperture Radars, which uses two different brands. So using that, they are going to capture complete image of the Earth periodically. So it is estimated to be around 14 days. For every 14 days, we are going to take a fresh radar image of the Earth. The project is yet to be launched. Yeah. These satellites are only to the particular spectrum. Yes. These satellites are only for a particular spectrum, wherein generally a single satellite cannot observe the entire electromagnetic spectrum. The maximum thing is we have the Astrosat by India. We'll discuss about it, wherein that uses X-ray, UV, and visible. But most of the times, generally we build a satellite in such a way that it observes one or two parts of the spectrum. Okay. Coming to the fourth question, most of you have answered D, few of you have answered C. All right. First one. Gaganyan will be India's first manned flight program. This is correct. So far, we have never sent astronauts to space. Mr. Rakesh Sharma, who was Indian Air Force pilot, he traveled to the space station called Salu 7. So this space station was owned and operated by the former Soviet Republic, which means Rakesh Sharma is the only Indian who has traveled to space. But he did not travel through any of the launch vehicles of India, wherein he traveled through the Russian launch vehicle because he traveled to the Russian space station. So when we launch Gaganyan, that will be the first manned flight program, no doubt. Second one. The orbital module of Gaganyan uses cryogenic engine for propulsion of service module as well as crew module. This statement is wrong. That's because for launching the Gaganyan, that is the entire launch vehicle, GSLV Mark III is going to be used. Right now, ISRO has an additional label. It's called as a human rated launch vehicle, which means it's capable or it is fit enough to send humans to space, which is just a modified version of GSLV Mark III. Now, GSLV Mark III uses cryogenic engine, no doubt. So the cryogenic engine in GSLV Mark III will be used for launching the orbital module, wherein once the orbital module is launched, it has two modules inside. One is called as the service module, that is the SM. The other one is called as the crew module, that is the CM. We have mentioned it here. That is the crew module and service module. So here what you have to understand is, crew module means this is the container where the astronauts will be present inside, which means it's a pressurized container with thermal protection systems. Where in service module means it contains additional engines and everything so that we can just elevate the module to different orbits because we are planning to send them up to 300 to 400 km. The altitude are not confirmed. So the service module will contain liquid thrusters. I repeat, liquid engines, not cryogenic engines, that will be used for elevating them. So in short, Gaganyan is going to be launched with help of cryogenic engine, but the orbital module will not contain cryogenic engine. The orbital module operates only based on liquid engines, not cryogenic engines. So the second statement is wrong. Coming to the third statement, Vyominoid safety is ensured by parachute deceleration systems which is developed by ISRO and DRDO. This is true. Recently they have tested it. That's because when the astronauts are dropped or when they are going to reenter into atmosphere, they face a lot of friction. So the crew module is safely encapsulated. It has to be decelerated because when it enters inside, it will have somewhere around 250 m per second. In other words, in four seconds, it will drop down at least 1 km. But you have to reduce it up to 11 m per second. This is the target set by ISRO. It has to be reduced up to 11 m per second before it splashes into the ocean. So how are you going to decelerate? We are going to deploy parachutes. For additional safety, we have additional parachutes also. If the main parachute is deployed, and then if it fails, there will be additional parachutes so that the astronauts will safely splash into the ocean so that we can collect the module and they will be returned safely. Third one is right. First one is right. Second one is wrong. Answer should be C. Can you go to the next one? Do you have any doubts in this? Okay. Coming to the next question. Fifth one. Related to deep space missionals. The first statement it says, no spacecraft has landed on Uranus and Neptune. This is true because the outermost planets, that is Uranus and Neptune, are only one spacecraft has visited it, which means it has not landed, it has not orbited, but it's a fly by spacecraft. It's called as the Voyager 2, which was launched by NASA in 1977. It is active till now because it uses radioisotropes for acceleration. Right now it's present outside the solar system. Now, Voyager 2 is the only spacecraft that has visited all the four Jovian planets, that is Jupiter, Saturn, Uranus and Neptune. So only spacecraft to visit all the four Jovian planets, Voyager 2 and also only spacecraft that had ever visited Uranus and Neptune, it is Voyager 2. So no spacecraft has landed, true. No spacecraft has landed in these two gaseous planets. First one is true. Second one, NASA was the first space agency to deploy a rotor-based spacecraft, in very simple terms, a drone. A rotor-based spacecraft on another planet, this is true. That's because in 2020, NASA sent a mission called Mars 2020. The name of the mission is Mars 2020, wherein it had a rover called Perseverance. So inside this Perseverance, we had a rotor-based, there is NASA sent a rotor-based spacecraft called Ingenuity. Wherein this is the first spacecraft that made a powered flight on another planet. Now the second statement is true. The name of the mission is Mars 2020, by NASA. And the name of the rover, the largest and heaviest rover ever sent to Mars, that is Perseverance. And then it had a rotor-based spacecraft that was called Ingenuity, 2021. It reached there in 2021. Now the third one, no space agency has landed on a comet due to high velocity and eccentricity of the object. This is wrong. That's because Rosetta Stone, mission by European Space Agency, it has landed on a comet. So only one successful landing, wherein there is one more mission called Vega, but the crash landed. Only soft landing on comet, it was made by the Rosetta Stone mission by European Space Agency. Mostly we send missions to asteroids, that's because they may be rich in metals or carbon or any other hydrocarbons, wherein European Space Agency, it landed once on a comet. So when we talk about the planet, should we include moon and not the planet? Ronuk Sir, no. When you talk about planets, we are talking only about the planets. But when you talk about planetary system, you can include moons. Or when you talk about solar system, you can include the moons. So one is correct, two is correct, third one is wrong. Answer is 1 and 2, and fifth one answer is A. Do you have any doubts on this? Can you go to the next one? And if you're wondering what exactly it means by eccentricity, eccentricity means how much the focus is offset from the ellipse. Let's say if this is ellipse and then the focus is present at the center, then this is like mildly eccentric. But if you take a comet, this has an orbit like this. It reaches very closer to the sun. So we call it as highly eccentric. So since it reaches very close to the sun, what happens? The temperature increases. And when the temperature increases, basically the hydrocarbons or ice, anything present in the comet, it burns and that gives the characteristic tail, the gas tail formed by the comet. So comets have highly eccentric orbit when if you take an asteroid, it has an elliptical orbit. If you take an asteroid, it may have orbit something like this. It will not approach very close to the earth. All right. Generally, asteroids are present in the asteroid belt or sometimes they may form frozen asteroids, which we will discuss later, wherein comets are formed in a place called Uth's cloud, which is present in the outer belt of the solar system. So outside the Kuiper belt, you have a place called Uth's cloud. This is where the comet forms. So the path of the comet will be somewhat like this. It reaches very close to the sun. And then again, it reaches the Uth's cloud. The third one is wrong. That's because one landing so far. The answer is one and two. Coming to the next question. All right. You know, honestly, most of you have answered A. Very good. The answer is A, Mangalyan. So the reason we took this question is, Mangalyan, when was it launched? It was launched in the year 2013. Reached in the year 2014. It reached Mars in the year 2014. Where in the estimated, the Mangalyan will survey for six months. It's considered to be a technology demonstration mission, which means it is said to demonstrate a technology. That's all. We expected it to operate for only six months, but it operated until 2022. Only during eclipse, we lost connectivity with the Mangalyan mission. The last year, they declared it to be completed. So these are the accolades that Mangalyan holds. First one, very rare phenomenon where China referred it as pride of Asia. That's because India was the first Asian country to successfully send a mission to Mars. Keep this in mind. India was the first Asian country to successfully send a mission to Mars. Second one is true. It got US based, National Space Society Award. That's because till date, it's also one of the most economic mission sent to Mars because it used a method called as Hormon Transfer Orbit. Repeat. It used a method called as Hormon Transfer Orbit. Which means, the first phase is geocentric phase. That is, the Mangalyan mission started orbiting around the earth. The first phase, it was based on earth. The second phase, after it gained enough acceleration, it was sent towards the Mars wherein this trajectory was based on sun. So the second phase was called as heliocentric phase. First, it orbited around the earth. Second one, it made a trajectory based on sun. And finally, it reaches Mars wherein it was captured by gravity of the Mars. The third phase is called as aerocentric phase. Mangalyan went through very less number of tests. So the overall budget of the mission, it was captured to somewhere around 450 crore rupees, which is very less compared to the other Martian missions. Since it was a very innovative method and also a very cost effective method to send it to Mars, it was given such awards. And also India was the first country to attain success in its maiden attempt. Be very careful when you read this statement. Because 2016 UPS equation it says, India is the only country that has attained success in its maiden attempt. That is the very first attempt. Wherein that was true till 2020, India was the only Asian country. Or throughout the world, India was the only country that has attained success in the Martian mission in its maiden attempt. Wherein, 2021, this record was broken by, or right now we can say the record is shared by, a mission called as Al Amal mission. Al Amal mission or sometimes called as Hope Mars mission. The importance of this mission is, this mission was built by United Arab Emirates. Wherein this was launched by Japanese Aerospace Exploration Agency. So the record that was exclusively held by India, right now it's a shared between India and United Arab Emirates. When you revise your old UPS equations, make sure that you understand, right now India is not the only country that has succeeded in maiden attempt. All the three statements are related to Mangalyan mission. Answer is one. Can you go to the next option? I mean the next question. Do you have any doubts on this? Okay. Next question is related to Sun. Most of you have answered A. First one, sunspots versus coronal holds. Two different phenomena that we have to discuss. First we'll talk about coronal holds. The concept of coronal holds. First thing you have to keep in mind is, the picture that you see here, you see certain missing portions or like darker portions in the sun. This is called as a coronal hold. But if you use a solar telescope and then if you're going to look at the sun, this won't look like this. Or in other words, coronal holds will not be visible because coronal holds are visible only in ultraviolet spectrum or sometimes in X-ray spectrum. It is not visible in normal light or visible spectrum. This is the first thing you have to keep in mind. But when we talk about sunspots. So sunspots, these are regions where the plasmas or the plasma flow is very less. These sunspots, they form in photosphere of the sun, the light layer of the sun. And this can be seen in visible spectrum. This is the first difference you have to learn. Second thing is, generally coronal holds. These are the places where solar storms will emerge from. So first you can write, coronal holds are generally associated with solar storms. They're associated with solar storms. Second thing is, these are formed generally when sun is having lesser activity or minimum solar activity. Lesser solar activity. All these are related to coronal holds. When we talk about sunspots, it can be seen in visible spectrum. It is seen in the photosphere layer. And very important, more sunspots are formed when sun is in solar maxima state. And these sunspots, they're mainly associated with particle events, particle events such as coronal mass ejections, where stream of hot or ionized particles will be emitted. Ionized or magnetized particles will be emitted from sun. The last year, we had a question related to the particle event from the sun. They've given like seven statements and they've asked, what are the effects that could happen if solar storm is reaching here. Understand, solar storm means it is generally created because of the coronal holds or wherever the coronal holds are present, wherein coronal mass ejections are created when sun is in maximum solar activity where more sunspots will be formed. And one more thing to understand here is sunspots, they're not permanent. Generally, they're formed near the poles, wherein sunspots can exist for a few days or sometimes for weeks or even for months. They're like a short time event. More and more sunspots will be created. There are times where sun will create more than 50 or 60 sunspots and then it disappears. So this is occurringly happens wherein coronal holds will sustain for a longer time compared to the sunspots. These are the differences. Based on that first statement, sunspots are dark and cooler areas on the visible surface of the sun caused by magnetic activity. First statement is correct. Coronal holds are cooler and less denser regions in the sun's outer atmosphere where solar wind can flow. This is also correct. I told you to associate coronal holds with solar winds and sunspots with coronal mass directions. So first and second are correct. Third one, coronal holds do not emit radiation. No, coronal holds emit ultraviolet and X-ray wherein sunspots emit X-rays. No, sunspots are regions. These are like swapped. Sunspots are regions where you will not have radiation. Where in coronal holds are regions where you will have X-ray and ultraviolet radiation. Third one is wrong. First and second are correct. Answer should be A. Answer for this question is A. Do you have any doubts on this, online people? This may be a bit tricky to understand, but make sure you do a retrospective research, search in current affairs, search in the Hindu newspaper, Indian Express, and also go through the NASA websites, you will understand.  If you're a GS student, you will receive it in the telegram channel by today. Please explain third point again. Sir, here I told you coronal holds are regions where solar storms will be emitted. And so the coronal holds will emit UV and X-ray radiation. Where if you take a sunspots, so these are regions with a very strong magnetic pressure where plasma will not flow. Or in other words, very reduced plasma flow or absence of radiation can be called as a sunspot. Which means here the statement should have been coronal holds emit X-ray and ultraviolet radiation while sunspots do not emit radiation. That should be the ideal statement, but here the statements are swapped. So the third one is around, clear? Any other doubts? Will the recording be uploaded? Yes, it will be available in YouTube and also we will send it through the telegram channel. Karthika Murugan, you have a question related to sunspots. See here, sunspots are regions where the magnetic pressure is more. And because of that, the temperature also will be lesser. Let's say this is the photosphere and chromosphere region. Let's say this is having somewhere around 6,000 Kelvin, for example. If you take the sunspots, these will have temperature of around 4,700 Kelvin or in other words somewhere around 4,200 degree Celsius. At least 1,000 degree Celsius lesser compared to other regions of the sun. That's because there is a strong magnetic pressure here. Imagine something is flowing out from here and then I put a pressure here. What will happen? Plasma flow will be obstructed and because of that, the temperature will be lesser and also the plasma concentration will be lesser. That's called as a sunspot. Is it clear? Causes for coronal holes. That's one mystery that the scientists are studying right now. You have somewhere around 20 plus heliophysics observatories that are performing research. It's a very lengthy topic wherein we have something called a solar dynamo mechanism or magneto hydrodynamic dynamo mechanism. There are different effects that explains this. That's a very lengthy topic. Let's not go into that right now. Coming to the next one. I think in previous years, UPS was giving questions related to the ELISA mission or sometimes they give you a random term or description of a mission and then they ask you what the mission is related to. Generally related to some international missions. Here, the key words that you have to pick here. The spacecraft will get boost from Earth's gravity to complete 12-year-old solar dynamo mechanism. Which means it's a very lengthy journey. Second key term here is asteroids. The third one key term here is Trojans. These are the three terms. So of all the missions, all these missions here, they are related to asteroids, no doubt. If you take Hayabusa, the answer is D by the way. But anyway, I'll tell you what are the other options related to. If you take Hayabusa 2, it is a mission that was sent by Japanese Aerospace Exploration Agency and this was sent to a single asteroid. It was sent to an asteroid called as Ryugu. It was sent to an asteroid called Ryugu. This is called as Ryugu, to collect samples and return. When it has returned during the Covid-19, somewhere in 2021, it returned samples. Right now, it is on an extended mission where it is traveling to a different asteroid right now. So, this going to one astroid, a collected sample, right it is traveling to other asteroid. So, it is not travelling to 70 Trojans, no doubt. Eliminate the first one. Asoiris Rex. This was a mission that was launched by NASA, wherein this was sent to asteroid called as Bennu, a carbon-rich asteroid called as Bennu. It has collected samples and it started its return journey in 2021, which means mostly by this year, mid of this year, samples from Bennu will be returned and it will be collected by NASA through the OSIRIS-X mission, but it is not related to the Trojan asteroids, because it has traveled to only one asteroid, eliminate this one. Dark mission often seen in the news. This is again not related to Trojans. This was sent to a nearest asteroid. Dark mission was sent by NASA again, wherein this was sent to an asteroid called as Didymos. We sent it to a binary asteroid, wherein we crashed the spacecraft. In other words, we made an impact using the spacecraft on the asteroid, that is, in future. If any spacecraft is going to or if any asteroid is going to approach the Earth, we try to divert it. That mission is called as Dark. So you can easily eliminate these three options if you have been following the newspaper, wherein the answer is Lucy. The importance of Lucy mission, first one, it's a first-ever mission that is sent to Trojan asteroids. First of all, we have to understand what are Trojan asteroids? So Trojan asteroids means they share orbit with the planet. Trojan asteroids, they share orbit with the planet. Asteroids that share orbit with the planet, you call them as Trojan asteroids. When in this case, if you take Jupiter, there are two points, that is Lagrangian point 4 and Lagrangian point 5, L4 and L5, these two places, asteroids will accumulate and they will not collide with the planet. That's because the planet is orbiting, the Lagrangian points are also shifting, which means they will share orbit with the planet, but they won't generally collide with the planet. Most of the planets have Trojans, including Earth. So far, we have found that Earth contains two Trojans. Now, we want to study about the Trojans of Jupiter. For that, NASA sent a mission called as Lucy. Now Lucy is going to visit both Lagrangian point 4 and Lagrangian point 5, L4 and L5 through a complex maneuver. It will take at least 12 years to complete it. Even though when they launched it, they said that there's seven asteroids or seven Trojans, but right now it is increased because certain asteroids are binary asteroids, two asteroids are binary. So they're saying it is going to visit nine Trojans. So the numbers are not important, but remember it's going to visit multiple Trojans in L4 and L5. The answer is D. Can we go to the next one? Okay. Coming to the ninth question. Just to understand this, first, there are these many elementary particles, wherein we are going to simply classify them into two types. First, you can write. I think online most of them have answered A. Okay. So, first, broadly, we are going to divide them into fermions and bosons. First, you can write. It's broadly divided into fermions and bosons. So, inside fermions, again, we are going to subdivide it into particles based on quarks and leptons, particles based on quarks and leptons, wherein these elementary bosons, they can be further subdivided into gauge bosons and scalar bosons. Note it. Okay. Now, if you see this picture here, first of all, we'll talk about quarks. So quarks are like building blocks of present elementary particles. That is, if you take protons and neutrons, for example, repeat protons, neutrons, all these are made up of quarks. That's because at least three quarks combine together to form particles like protons and neutrons. In other words, headrons. Headrons means heavier particles, repeat. Headrons, such as protons and neutrons, they are made up of quarks. There are six different types of quarks. We have up-down, charm, strange, top, bottom. We don't have to dwell into the details right now. Wherein if you take leptons, lighter particles fall under leptons. If you take electron, for example, they're not made up of quarks, but they fall under fermions. So electrons are the opposite to it. What we call as positron, E plus one zero or anti-electron. All these fall under leptons. Now, coming to these, that is the gauge bosons. Then if you see here, all these are gauge bosons, blue bonds, photons, z bosons and w bosons. These fall under gauge bosons. Where and what is the use of this? Do you remember when we discuss about four fundamental forces? First is gravitational force. Other one is strong nuclear force, and then you have weak nuclear force, and then electromagnetism. Wherein gluons are related to strong nuclear force. In other words, strong nuclear forces mediated by exchange of gluons. Wherein these two, that is z bosons and w bosons, these two are related to weak nuclear force or weak interaction, which means this is responsible for nuclear decay and also for nuclear fission and fusion. Wherein photons, they are responsible for electromagnetism. All electrostatic force, electromagnetic force, they fall and they are mediated by photons. Wherein out of four fundamental forces, I have given you only three. There is strong nuclear force, weak nuclear force and electromagnetism. What is missing here? Gravitational forces missing here because there is a theoretical particle called as graviton. It is not a detector, it is only hypothetical. So, which also falls under gauge bosons. Now, coming to the Higgs boson, very important since noble price was given for discovery of this one. Higgs boson, you can write, they are providing mass to the particles. Repeat, they provide mass to the particles, which means there is an invisible field in the universe called as Higgs field. Any particle that is interacting more, it is going to gain mass or any particle that is interacting less, it is going to gain lesser mass. This is the basic. So, quarks will make protons, neutrons and heavier particles. Wherein, leptons make lighter particles such as electrons and then anti-electrons such things. Wherein, gluons are related to strong nuclear force, photons are related to electromagnetism, bosons are related to weak interaction and then Higgs bosons are related to mass. Based on this, if you read this one now, protons and neutrons are bosons. See here, protons and neutrons are bosons, no wrong. Wherein, photons are fermions. It is basically swapped, that's because protons and neutrons are fermions. Wherein, photons fall under bosons, which means the first statement is wrong, it is swapped. Protons and neutrons are fermions, while photons are bosons. Second one, Higgs bosons is responsible for giving mass to the particle, this is true. Higgs particle and Higgs field is responsible for providing mass. Third one, the universe has equal amounts of matter and antimatter, this is wrong. That's because when initially when the universe formed, every particle they had an opposite particle. If there is a proton, there used to be an anti-proton with opposite charge. For electron, there was an anti-electron or otherwise called as positron. Even for neutron, there was an anti-neutron. Every particle had equal or opposite particle that differs only by one number. Wherein, at some point of time in the universe, slowly matter took over. Wherein, the entire antimatter is destroyed. So right now, we don't have antimatter, at least for a stable amount of time. So antimatter is only created in the labs right now. Labs like CERN, they have antimatter and very small amount in few milligrams. Wherein, generally in the universe, 99.99% is filled only with matter. Wherein, antimatter, even if it is formed in the universe, it's not reasonably stable for a longer amount of time. So this one is wrong. And by the way, the reason why antimatter disappeared and why matter formed, it's a very lengthy topic. Wherein, it's called as barogenesis. Or otherwise, this is called as the charge parity violation. The event is called as CP violation. There was a violation that happened in the universe that slowly led to the complete destruction of antimatter and matter took over the universe. So third is wrong. First is wrong. Only second is correct. Answer is B only. Compared to all the previous questions, this is a bit tougher, I understand. But because we have finished space science followed by astrophysics, and then we have to step into other topics. So generally the end of each topics will be a bit tougher question. Coming to the 10th question about stars. Okay. Many answers for question. This particular question is deep. Most of you have given the answer. First one, sun is a main sequence star. This is true. It's composed of 91% hydrogen and 8.9% helium by number, not by mass. First one is wrong. Because if you take sun, see here, we'll talk about hydrogen and helium. There are two things that you have to consider. First is based on number. The second one is based on mass. So if you take in terms of number, hydrogen will be 91%. And then helium will be 8.9%. No doubt. The figures are correct, but it's based on number. That is, if you're going to take particles, if you're going to count them, 91% of the particle will be hydrogen and 8.9% of the particle will be helium. That is correct. But if you take it in terms of mass, hydrogen is H11. It has only one proton and one electron. But helium contains two protons, two neutrons and two electrons, much heavier. So in terms of number, they may be lesser. But in terms of mass, they are higher. So this contributes to somewhere around 70.6% when this contributes to somewhere around 27.4%. Most of them together will contribute around 98%. wherein other elements will form rest of the particle. In this case, first one is wrong. Till the last word you have to read, when it's not based on number, they've given it's based on mass. So the first one is wrong. Second one, sun can neither undergo supernova explosion, nor form a black hole. This is true. That's because only massive stars, they can undergo supernova explosion and then it can result in black hole. To understand this, first you have to see this picture wherein left hand side of the picture taken from NASA, this is related to an average star wherein right hand side of the picture that is related to massive stars, left hand side, average star, right hand side, massive star. Now if you take an average star, the top portion of the chart, initially the star starts from a region called as nebula, basically the collection of gases and dust particles. And then it will form a structure called proto star, a form before the star, followed by that every star that is an average star or even a supermassive star, first it will form main sequence star. I think in the previous statement you would have read, sun is the main sequence star, sun is in this phase right now. And then on undergoing further fusion reaction, average star like sun, I repeat, average star like sun, it will become a red giant and followed by that it will undergo a implosion process called as planetary nebula. And finally it will form white dwarf, I repeat the end product of sun will be white dwarf. Right now it's in main sequence phase and then it will progress into red giant followed by planetary nebula, it is going to form only white dwarf wherein if you take a massive star, I'm going to talk about a massive star, massive star means stars that may be up to five times the mass of sun, M0 stands for solar mass, by the way M0, approximate value of M0 or estimated value is 2 into 10 power 30 kilogram. Now if some star has mass more than five times the mass of sun, then you call it as a massive star. Now if a star is massive, then it will undergo a process called as supernova explosion. And after supernova explosion happens in the star, that is towards the end cycle, there are two possibilities, first possibilities it can form a neutron star, second possibilities it can form a black hole. Now supernova explosion happens when something like this will happen, that is starting from the outer layer, hydrogen all the way till iron, Fe 2656 will be formed in the star. You see here, outer layer is hydrogen fusing shell, for the people online I will just zoom this, see here outer layer is hydrogen fusing shell, when the center most layer is iron core, when iron is formed the further fusion cannot happen and because of this the star will implode followed by that there will be highly energetic explosion. So this explosion is called as supernova explosion, I repeat this explosion is called as supernova explosion. So after supernova explosion happens there are two possibilities, the star can either become a neutron star or it can form a black hole, if it is massive enough it will form black hole or otherwise it will form a neutron star. Now this may be very vague especially for non-GIA students who are attending online but when you go through the image you will understand, first we are talking about average star like sun, starts from nebula, it becomes proto star, then it becomes main sequence star, then it becomes a red giant, undergoes implosion, it forms white dwarf. So any average star like sun it will form only white dwarf, it will never form a neutron star, it will never form a black hole but if you take a massive star, this will undergo supernova explosion and it can form either a neutron star or a black hole. Based on this, read this statement, sun can neither undergo supernova explosion, true because sun can neither undergo supernova explosion nor form a black hole, not possible, only if a star is like five times more than sun it can undergo supernova explosion and it can form a neutron star or a black hole. So this statement is correct, second statement is correct, no elements heavier than iron can be formed in core of the star before supernova explosion, true the maximum element that the star can fuse and form it is iron and after that all the heavier elements that are starting from atomic number 26, all the heavier elements will be formed only by supernova explosion, two and three are correct, first one is wrong, answer is B, answer for this question is B, astrophysics will be like one least touched topic by the aspirants but at least there will be one to two questions regularly, question about theory of relativity, question about collision of black holes and then questions about experiments like LIGO, these are repeatedly seen, so make sure you understand about the star system. Can we go to the next one, which one undergoes supernova explosion, Dhanapriya ma'am, generally supernova explosion happens in massive stars, massive stars undergo supernova explosion, average stars undergo only Plan 3 nebula followed by white bar, online people do you have any doubts, can we go to the next one, okay coming to the next question, all right most of you have answered B, few of you have answered A, okay, so first let's understand what exactly is gravitational wave, please understand gravitational wave is different, the force of gravity is different because gravitational waves are more like a shock wave, that is if you are going to clap your hands what happens, it just vibrates the air molecule, so similar to that when astronomical objects are spiraling on each other and then if they are going to colloid with each other, so this collision will create a shock wave, so these shock waves are called as gravitational waves, so even though I'm using the term shock wave ideally it should not be called as a shock wave because a shock wave can happen only when there is a medium I understand, but only for a comprehending purpose, imagine it like a shock wave that is created when two objects are colliding with each other, now the first one gravitational waves are created by binary star systems colliding with each other, the one you saw in the animation, first one is true they're asking which is incorrect statement, second one gravitational waves travel at the velocity of light, interestingly this is true, most of you have answered b but understand gravitational waves, these are created when there is a highly cataclysmic event or a high energy event and it travels with velocity of light, currently the only type of gravitational wave that have been detected are compact binary inspirals, this is also true, so which one should be wrong, d is wrong answer for this one is d, before that I'll explain the third statement, generally gravitational waves are divided into two types, first one is continuous gravitational waves which are created by a single object, let's say fast spinning neutron star or any single object if it creates a shock wave or a gravitational wave you call it as a continuous gravitational wave, the second type is transient gravitational wave, wherein GS students you would have written it as compact binary inspirals, compact binary inspirals, stochastic ring gravitational wave, all of them they fall under the roof called as transient, so transient means even that happens for a short time and that creates a ripple, so all the GS nodes we have written it's valid but still they fall under a general category called as transient gravitational wave, now the compact binary inspirals, it's a type of transient gravitational wave because compact binary, binary means two, so this is an example for compact binary, two stars orbiting, it's a binary system and then they get compacted and then they colloid with each other, so this is called as compact binary inspiral which is a type of transient gravitational wave and till date we have detected only the transient ones, the LIGO which is seen in news often 2016, 18, 21, they repeatedly detected the gravitational waves but these are from collision of neutron stars or collision of black holes which means generally binary systems are involved, so the third one is also correct but the fourth one is wrong because gravitational waves are predicted by Mr. Albert Einstein by the general theory of relativity, where in what I've given here modified Newtonian dynamics, this is a theory that gives an alternative explanation for source of the gravitational waves but till date till now the most widely accepted one is the general theory of relativity given by Mr. Albert Einstein, 2018 UPS equation go through it, they would have asked which of the following are predictions of general theory of relativity, answer here is D, D is wrong because gravitational waves are predicted by general theory of relativity for the first time by Mr. Albert Einstein, can you go to the next one, sir but black holes gravity can easily stop light, so see here Karthik when something is entering into black hole it's going to be stopped but when two black holes colloid they will create a shock or they will create gravitational wave which will travel, so you'll understand about it when we go through the next question, take a look at this one, first one black holes have infinite volume and infinite density, you would have fallen for the term infinite but this is wrong, black holes have infinite density that's true but they don't have infinite volume that's because volume is expressed in meter cube, see here SA unit of length is meter, SA unit of area is meter square and SA unit of volume is meter cube which means only when something is three-dimensional you can calculate volume wherein if you take black holes how we predict black holes is everything that has every matter and radiation, all of them they get compressed and they are stored in a single point, so black holes are generally said to be a point mass, when you say the term point it means a single dot, it's a two-dimension one wherein it's a single dimension where every mass is compressed inside, so black holes have zero volume but infinite density, it may look like a misnomer or very contradictory but this is the general characteristic, black holes do not have volume, if you have been imagining black hole like a spear understand the field of influence of black hole can be a spear but the actual black hole is just a dot, so the first statement is wrong, the probability of finding a supermassive black hole at center of a supermassive galaxy is high true, the reason discovery is almost all the supermassive galaxies have a supermassive black hole present at the center, best example is Milky Way, if you take the Milky Way which is a spiral galaxy for example but I'm generally drawing it as a ellipse only for understanding purpose to make it quick, if you take this is Milky Way, the center of the Milky Way it has a black hole called as Sagittarius A star, often seen in news because noble price for physics for the year 2020 was given for discovery of this one, so most of the supermassive galaxies will have a supermassive black hole especially at the center, second one is correct, third one black holes are formed when stars reach Chandrasekhar limit, no, if you remember the previous question related to the stars, see here we discussed about a star system called as white dwarfs, Chandrasekhar limit is related to white dwarf I repeat, Chandrasekhar limit was predicted by Indian born astrophysicist Mr Subramaniam Chandrasekhar, it is only related to white dwarf keep in mind it is nowhere related to a neutron star or a black hole, now what is Chandrasekhar limit is, let's say white dwarf starts gaining mass from the surrounding particles, wherein Mr Subramaniam Chandrasekhar he predicted the maximum, wait me a minute, the maximum mass of a stable white dwarf, that is how much a white dwarf can hold the mass, the maximum amount of mass that is predicted to be 1.4 times the mass of sun, I have already given you the mass of sun that is 2 into 10 to 30 kilogram, so this 1.4 into M0, this is called as Chandrasekhar limit, so if there is a white dwarf and if it is going to take matter from the surrounding areas including stars and then if it breaches this limit, this will again explode, that's a different type of explosion, so Chandrasekhar limit is not related to black hole, it's related to white dwarf, fourth one, two neutron stars can merge to form a black hole, that's possible, I told you in a star explodes it can form neutron stars, now imagine two neutron stars colliding with each other, the animation that you see here, this can lead to formation of a black hole or this can lead to formation of a larger neutron star, both can happen, so two neutron star can combine to form larger neutron star or two neutron star can even combine to form a single black hole and again two black holes can merge to form again larger black holes, all these are astronomical events, now this is true, first is wrong, second is true, third is wrong, fourth is true, which means two statements are correct, answer is B, do you have any doubts in the 12th one, okay can we go to the next one, yeah coming to the, and by the way someone was asking related to the black hole, who was it Karthik sir present online, see here, if you take a black hole, this is the point mass which we are discussing about, the centermost part of the black hole, it's called as a singularity, the place where everything gets compressed to a tiny point, wherein if some light or if some particle is traveling near the black hole, there is a maximum limit, so if it is going to enter inside for example, if it is going to enter this limit, it gets trapped inside, but if it is passing near the limit of the black hole, it will bend, but it will not be trapped inside, so this outermost border is called as event horizon, so I repeat center part is black hole, the outermost field of influence is called as event horizon, and the distance between the black hole and the event horizon is called as square shield radius, because it's a scientist who predicted radius of the black hole, so three terms you have to remember, first one, the actual part of the black hole is called as singularity, and then outermost field of influence of the black hole that's called as event horizon, imagine it like a border, imagine a cricket ground and then at the center of the pitch you are going to place a piece of grain for example, so that grain will be black hole, singularity, wherein the grain has influence throughout the stadium, so the outermost border of the stadium you call it as the event horizon, the distance between center of the sand and the outer part of the stadium you call it as square shield radius, three important things you have to learn for this balance, clear? Okay, coming to the next question, 13th one, so we have completed space and astrophysics, next we are going to nuclear science, all right we'll start with the first statement, India's three stage nuclear program will use fissile isotopes of uranium and plutonium as fuel, this is true, if you have been wondering why thorium has been eliminated we'll talk about it, because thorium is not directly used as a fuel, thorium will be converted into uranium and then it will be used as fuel, so three stages, first is stage one, next you have stage two, next is stage three, it's a very lengthy topic, I will give you all the three key terms, non-GS students, you can just go through it in internet or you can go through the website of department of atomic energy, stage one, India uses pressurized heavy water reactor PHWR, stage two, India uses fast breeder reactors and in stage three, India is planning to use advanced heavy water reactors, AHWRs, now the fuel that we are going to use in stage one will be, we are already in stage one, uranium 92, 235, fissile isotope of uranium is used as fuel, wherein in stage two, we will be using plutonium 94, 239 as fuel and then in stage three, again we will be using plutonium 94, 239 as fuel, so while the stage three is running, the thorium which is abundantly present in India, the last year UPSI question, wherein thorium is present throughout the eastern coast and then in Malabar coast, not in the entire eastern Indian coast, it is present only in the, present in entire eastern Indian coast and then only in Malabar coast and if you are wondering where it is present, it is present in the beach sands, what we call as the monazite sands and then the highest amount of thorium is present in Andhra Pradesh by volume or by mass, the highest amount is in Andhra Pradesh, followed by that it is present in Tamil Nadu, followed by that Odisha, followed by that Kerala, followed by that West Bengal, followed by the Jharkhand and other states, so this is the general concentration, about 30% is present in Andhra Pradesh, Andhra, Tamil Nadu, Odisha, Kerala, West Bengal in decreasing order, now we will be extracting thorium from the monazite sands, somewhere around 30% of the monazite sands will be thorium and after extracting thorium, you will be using in stage three as a neutron absorber, not as a fuel but as neutron absorber, so this thorium 90 232, this will be bombarded by neutron, we will be creating arrangement for this wherein this will transmutate into uranium 92 233, repeated forms uranium 92 233, not to be confused with 235, now this uranium 233 will be again used as fuel in stage three, after removing plutonium, after few years, we will be changing the fuel to uranium 233, so with respect to the first statement, India's three stage nuclear program uses fissile isotopes of uranium and plutonium as fuel, it is true, stage one uses U 235, stage two uses plutonium 239, stage three uses plutonium 239 and then followed by that it also is going to use uranium 233, generally different isotopes of uranium and plutonium is used. Second one, India can indigenously build nuclear reactors required for three stage nuclear program two, initially we had dependence on Canada, the first reactors where it can do reactors but right now of all the reactor technologies available in India, India can indigenously produce these two types of reactor, the pressurized heavy water reactor used in stage one and then fast-beader reactor used in stage two and advanced heavy water reactor, we have just a test reactor based on that we will be building larger reactor at a later stage, so all the reactors required for three stage nuclear program can be indigenously produced in India and this is very important for upcoming problems that's because India's largest pressurized heavy water reactor, this is located in Kakrappa, in Gujarat Kakrappa unit number three, this has 700 megawatt energy capacity and right now it's functioning, even a prime minister posted a congratulatory tweet for this because it's a shining example for making India a campaign, so India is capable of producing these two and if you have marked it to be a wrong statement, thinking about dependence on Russia or thinking about dependence on Canada, understand for pressurized water reactor, PWR, we depend on Russia, the reactors located in Kudankulam for example those are pressurized water reactors but mostly India has PHWR which can be produced indigenously, FBR which is present in IGKAR, Indra Gandhi Centre for Atomic Research in Kalpakam which can be produced indigenously, so which means the second statement it becomes correct, third one, the prototype pass-beter reactor will advance nation into second stage of three-stage nuclear program not third stage, the answer is one and two only, A is the answer, do you have any doubts in this, can we go to the next one online people, would you please repeat those names Ashwin sir don't worry, all these names are present here, when you receive the slides you will you can go through it, any other doubts here, coming to the next question 14th question many of you have answered A, few of you have answered B, very few of you have answered D, okay the main reason if people would have chosen A is you would have wanted to eliminate the term violet because quantum computers will it violate certain properties where in this case first one is correct, quantum computers they violate bell inequalities, noble price for physics for the year 2022, it's given related to inequalities, second one entanglement property, so before you understand this first let's talk about the bell inequalities, so the concept of bell inequalities so given by a scientist called Bell in late 1960s based on a concept called as local realism, so the local realism says that is if there are two particles that are separated by a distance, these will be independent, on other words you cannot predetermine state of one particle based on the other particle, on other words particle exists independently, this is called as a bell inequality, it's a very lengthy concept but I'm just summarizing it in a very crisp manner or in very short manner for understanding purpose, so you have two particles, the one one particles state will not be dependent on the other particle, this is bell inequality, when when you talk about quantum computers, quantum computers mainly work based on two principles, first one is called as entanglement, in fact first you can write superposition followed by entanglement, sorry you can write superposition followed by that entanglement, so first when we talk about superposition, the idea is generally if you take a binary bit there can be only two states that is either it will have one or it will have zero, any one at a time but it's not possible to have one and zero simultaneously, this is possible in a binary computer that uses a transistor but this is not possible but when you take a quantum computer the bits can have simultaneous states that is it can be in a form of one and zero simultaneously, this property is called a superposition, the property by which two particles can coexist simultaneously in a single state that's called as superposition, now this superposition is achieved using something called as entanglement, so entanglement means something that is very connected, so how we can achieve entanglement, two different possibilities, first one there are many possibilities but I'll tell you an example, let's say you're generating two electrons using some method you're generating two electrons, electron number one and then you have electron number two, now the electron number one it has a spin quantum number of plus half and electron number two it has a spin quantum number of minus half when they are created one is having positive half the other one is having negative half and after creation I'm going to separate them, this is going to be separated somewhere or this is going to be kept somewhere, so I have electron number two and electron number one that are separated from each other, now the state of electron number two if it is in spin negative half I can automatically say the other electron that is electron number one should be in plus half, so I'm predetermining if I know the state of this electron I know the state of other electron, this property is called as entanglement, even if you're going to physically separate materials or particles state of one can determine the state of other this is called as entanglement, there are many possibilities even you can even use a light polarization that is given in the Nobel Prize citation here, let's say one light is polarized by 45 degree the other one is polarized by 90 degree from a single source, now if you know that this light is in 45 degree the other light should be in 90 degree, so the state of one light is determining the state of other light, so polarization of light or photons that make the light or electrons any such particles or wave can be used for creating entanglement, now based on this first one it's true because one state is predetermining the state of other one which is violating the belline equality first one is true, second one entanglement of photons or electrons can be used to create quantum computers true, you have quantum computers created by IBM Google few of them use light few of them use electrons, possible third one quantum computers cannot be built without superconductors this is wrong generally superconductors are used because if you have a superconductor wherein there's a string of positive charge like this negative charge will move in pairs inside entangled pair of electrons will move inside which means one will have positive half the other one will have negative half generally superconductors are used to build quantum computers but there are many other technologies they are something like ion trap technology there are many other technologies where quantum computers can be developed without superconductors also so which means this one is wrong one and two are correct answer is b one and two only fully confused with quantum computers don't worry cardix mostly if at all they want to ask they won't dwell into the technical details because it will look like a pure science paper three things that you have to remember whenever you learn about so if you see the last year they simply asked what's mean big qubit which is a quantum bit the one that I described here this is a binary bit wherein this is a quantum bit where in two can exist simultaneously so the application of quantum computer is you're going to quadruple or you are just going to multiply the computational power of a computer that's because which can exist simultaneously in two different states which means very complex algorithms and everything can be calculated by quantum computers now when you learn about quantum computers three things one is quantum bits which can use a electron or it can use a light in this context please read about quantum key distribution tested by where in India exchange to quantum keys so first you have to understand binary bit is different from quantum bits that's the first thing second thing how the the process or the phenomenon by which two different particles can exist in similar state that property is called a superposition when you subject light to interference or something it can have similar state so the state is called a superposition superposition is achieved using entanglement so entanglement means particles attached to each other or one particle influencing other particle entanglement is used to create superposition which is used for calculation this is the only thing you have to remember or otherwise you don't have to confuse much about it when the advantages first it's very powerful second thing it's very secure because if you are you going to use quantum key distribution for example if you're using light if someone tried to intercept it you can easily detect it so advantages it's very secure very complex problems can be solved these are the advantages when it comes to disadvantages it's quite expensive and then if you want to maintain a superconductor for example again it's going to be expensive and energy intensive process and the technology is very primitive not accessible for a common man these are the disadvantages this is sufficient can you go go to the next one take a look at this since you asked about belline equalities first read the novel play citation then I'll tell you the next okay based on this it's violating belline equalities because belline equalities based on local realism local realism says physical states are predetermined and the measurement of properties of one should not depend on distance between them but in here it depends because if one electron is having positive half spin another one is having negative half spin clear when there is one more question here sir what is india's quantum computer development program it's called as q u i c that is quantum it's located in raman research institute it's called as q u i c quantum information and computing lab the name of the lab is q u i c is it clear we'll go to the next one okay coming to the next looking at the answers you have given taken from ncrt most of you have answered a bc all mixed okay the answer for this one is a taken from your carbon compounds ncrt the last year we had a question from hydrogen compounds related to water water being a dipolar solvent but in here it is related to carbon so diamond graphite both consists of carbon atoms no doubt carbon has a valence of four it can form four bonds and why do they exhibit distinctive physical characteristics despite having identical chemical properties first one so diamond it forms a 3d structure which means every carbon will form single bond that is the carbon forms single bond with the surrounding atoms and it forms a three-dimensional lattice when if you take graphite carbon will have double bond like seen here carbon will have double bond and very important it forms hexagonal array the earlier one is 3d array and the graphite forms hexagonal array so only because of this the overall physical structure changes while the chemical properties are similar wherein how you have to eliminate this particular option is first one graphite and diamond are made up of different isotopes of carbon no both of them are made up of pure carbon c612 no doubt graphite contains additional impurities while diamond is made of carbon no both carbon and graphite generally they are considered to be pure forms of carbon only the physical characteristic will change now this could be a bit confusing varying temperature for formation of graphite and diamond diamond here varying temperature is required for formation of graphite and diamond there is no doubt in that but that does not account to different physical properties because graphite will be formed sooner wherein diamond requires more pressure and more temperature so no doubt varying temperature is required for formation of graphite and diamond but this statement d1 though this may be true this doesn't explain this question wherein the optimum answer should be a there are many questions in upc where you will get the options like this two options may look like a very correct statement but you have to link it with the question a is the correct answer d is wrong even the individually this statement is correct for this question answer is e finally explain the third one graphite contains additional impurities while diamond is pure so for the question arun kumar sir both diamond and graphite they are pure both are made up of only carbon atoms it's not about purity it's only about the physical structure aswin is it clear arun kumar all mixed mostly b and d options were given by people online now here first unlike cryptocurrencies each nft there is a non-fungible token is unique this is the keyword yes it is unique and cannot be exchanged for another nft of equal value this is also correct both may have equal value but still we cannot exchange exchanging means let's say person a and person b if person a has a image and person b has a image you're going to transfer like this this is exchange or more like a swapping this can never happen now how the transaction will happen is if a wants to buy a image from i mean b wants to buy a image from a first the money will be settled generally in form of bitcoin or any cryptocurrency and after that it can be transferred so transferring is different from exchanging transferring means you're not getting equivalent amount of some other object but here you're getting money and then you're transferring it so the first statement unlike cryptocurrencies each nft is unique and cannot be exchanged for another nft of equal value this is true if it is of equal value you can transfer it after getting a cryptocurrency that is possible but it's not exchangeable on other words if you take a currency currencies are considered to be fungible which means if you have a hundred rupee i have a hundred rupee if you're going to swap the money that's not going to cause a change both of them looks alike so exchanging them does not change the legal tender value that is called as a fungible one the currencies are fungible but when you take nft these are not fungible if i have an image that's cryptographically coded and it is stored in a blockchain so this cannot be exchanged but it can be transferred after getting a cryptocurrency first one is true the ownership and transfer of nft are recorded on blockchain network true making them transparent and immutable so most of you would have chosen the second one to be wrong because it says it's transparent understand the transactions are transparent but the users are anonymous which means every transaction is recorded on a distributed network or distributed block which is a public register basically everyone knows that a transaction happened but no one will know the details about the transaction so transactions are transparently recorded and also it's immutable which means it cannot be edited it is a permanent record once it is done it cannot be edited maybe you can initiate a first transaction but you cannot basically edit it this is the characteristic of the blockchain itself it is transparent that is the transactions are transparent and then the records are immutable and then the users are anonymous second one is true it's possible to create nft using both tangible and intangible items true it includes everything so if you see this one this is just a picture of rose it's a tangible one but they took a photograph of this and this was sold for somewhere around 1 million US dollar for a Valentine's Day because nfts are very costly and more than this this was sold for more than 1 million it's just a graphic art so any tangible and intangible which can include art or a graphic art or a photograph or even music video anything that is tangible can be cryptographically coded into nfts including a land record for example if you physically own an apartment you can take picture of the apartment and then you can make it as a nft it is possible so both tangible and intangible can be made into nft answer is d all the above so many questions that may rise from this particular one how tangible one if i have a physical object let's say i have a physical object like this so i'm going to convert it into a image and then if i'm going to cryptographically encode it i can call it as nft i exclusively own image of this particular presenter wherein one more person cannot create a replica that there should be a minimum difference let's say it can have additional buttons or have a different color so which means exact replica of nft cannot be created any doubts for this one can we go to the next one all right coming to the first statement radio wave has the highest energy in the electromagnetic spectrum no in the entire electromagnetic spectrum energy repeat the energy it increases from left to right which means radio has the least energy wherein gamma has the highest energy on other words energy increases from left to right compared to radio micro has more energy compared to micro infrared has more energy compared to infrared visible as more energy so you can simply write first one energy is lower here when on the right hand side the energy increases next when we discuss about this red light carries more energy than blue light it's wrong that's because visible the part of the electromagnetic spectrum that can be seen by you it's called as visible now you have to write it this way near infrared you get red near ultraviolet you get violet which means the width gr goes like this now violet is closer to ultraviolet which means it's more energetic red is closer to infrared which means it is less energetic we generally think red is very energetic but understand red has a longer wavelength so that it can travel for a very long distance without undergoing scattering but that doesn't mean they are very energetic compared to all these violet indigo blue are more energetic wherein wavelength will be lesser so this one is wrong or if you will be confused we can write this one dear students you would have been very clear in this topic but anyway for other people attending online you can write in the entire web jar if you take violet energy will be higher wavelength denoted by lambda will be lower and then frequency how frequently the wave will repeat this will be higher when if you take red you take red energy will be lesser wherein wavelength will be higher and then frequency will be lower if you want to visually represent this you can write something like this violet will be like this wherein red will be like this the wavelength is longer but the frequency is lesser and also the energy is lesser which means second statement is wrong first statement is wrong second statement is wrong coming to the third one all the electromagnetic waves are ionizing radiation no only certain electromagnetic radiations are ionizing in nature if you take gamma rays this can lead to genetic damage and cancers ionizing x-rays ionizing high energy ultraviolet rays not all ultraviolet rays are not ionizing in nature but only high energy ultraviolet rays are ionizing in nature which means the third statement is also wrong answer is D all the statements are wrong is it clear can we go to the next one all right coming to the 18th question we are coming to the biotech path now the D option says three only sorry it's hidden here online people what are your answers most of you have answered D few of you have answered the okay so first let's understand what exactly is mean by passive immunity immunity in human body can be broadly divided into two one is called as active immunity the other one is called as passive immunity the active immunity means in situ production of antibody or in other words your body is going to produce antibodies that will oppose the antigen so if it is produced at the site or if it's produced inside an organism you call it as active immunity where in passive immunity means generally ex situ production of antibody on other words we can say ready made antibodies those are called as passive immunity now based on this activists produced in the body passives produced outside the body first one antibodies produced by D lymphocyte this is a active immunity because D lymphocyte is a type of white blood cell that produces antibody in your blood which means it's a active immunity second one mother's milk or colostrum this is a passive immunity because initial time the babies may not be able to produce a lot of immunity so the mother's milk it contains a lot of immunoglobulin immunoglobulins or otherwise called as antibodies which means mother's milk is an example for passive immunity vaccines many of you would have chosen vaccines as passive immunity but understand vaccine is the active immunity which means vaccines are taken from external source but they trigger antibody production in your body which means vaccines even though they are external sources they are active immunity more like vaccine is a tool to induce your B and T lymphocytes so that's a passive immunity CAR T cell therapy recently seen in news chimeric antigen receptor T cell therapy that's because the first CAR T cell therapy was conducted in Tata Memorial Hospital in Mumbai what happens here is let's say a patient is affected by cancer now you're going to extract T cells from them that is the T lymphocytes are extracted and then you're going to insert a gene more like it's a somatic gene editing the white blood cell you're going to cause a genetic change you're going to encode certain information so that it can fight the cancer cells and after inserting the gene you're going to produce more and more of these cells and then it's infused into the same person repeat the person from whom the T cell was initially taken the T cell is modified more T cell is produced and then it's infused into the same person this is called as chimeric antigen receptor T cell therapy it can target the cancer cells it will bind to the cancer cells and it will kill them wherein GS students pay attention I would have told you CAR T cell therapy is a type of passive immunity but please change your GS notes CAR T cell therapy is treated as a active immunity even though it involves a heavy gene editing and everything while few newspapers have written it as passive immunity that's why I told it in class apologies for the error please change it anyway I'll be posting telegrams and also CAR T cell therapy even though it involves external sources it is treated as active immunity because the T cell is initially taken from one human and then that is modified and then it's infused into the same human which means the base for the immunity there is a T cell is produced in the body for that reason the medical community considers CAR T cell therapy as active immunity so the answer for this one is two only GS students make sure or ensure that you change in biotech topics we would have written it as passive immunity write it as active immunity answer is two only can you go to the next question coming to the 19th question well many of you have answered mostly have answered D few of you have answered C okay first statement 5G will use radio as well as microwave this is true that's because you would have familiarly studied that 5G uses three different spectrums it uses a low band mid band and a high band on other words it uses sub six gigahertz that is a low band and then followed by mid band followed by millimeter wave or otherwise called as high band this millimeter wave it basically falls under the microwave part of electromagnetic spectrum so even though it's generally called as radio spectrum auctioning for the government convenience understand 5G it uses higher bandwidth or millimeter wave which falls under microwave 4G does not use mic millimeter wave 5G uses millimeter wave which is a part of electromagnetic spectrum which is to be labeled as microwave now first statement is correct coming to the second statement 5G internet will have lower latency latency or other words called as ping which means if you have a device and then you're sending information or you're sending a query to the server the time taken to fetch the data back that's called as a ping or a latency wherein the second statement is wrong because any day fiber optic internet will have very lower latency for example if you are very closer to the server the latency can be up to 1 millisecond within 1 millisecond you will send a query and then you will you will get the result that is fetched from the nearby server so any day the only advantage of 5G here is comparatively lesser latency compared to the 4G it has very lesser latency and very important thing is it is wireless that's advantage wherein any day a LAN cable connected to your computer is going to be much faster latency is going to be much lesser second one is wrong third one the range of millimeter wave used by the 5G is limited to smaller space this is true that's because if you imagine this to be a room for example let's say I'm sending the low band mid band and millimeter wave so low band will have the least wavelength which means it can easily penetrate through the walls mid band comparatively lower wavelength and higher energy this can also penetrate through the walls but if you take the millimeter wave which is a microwave it has very short wavelength which means the throughput or in other words data transfer rate the data transfer rate is going to be much higher but the penetration is going to be again much lesser so higher the data speed lesser the penetration wherein lesser the data speed greater is the penetration because the wavelength is longer it can pass through opaque surfaces like a wall or a building but if the wavelength is lesser and energy is high only for a short space you can use it on other words if you look at this one it says frequency increases penetration decreases so millimeter wave the frequency is higher like I've given here the frequency is higher but penetration is lesser when if you take a low band the frequency is lesser but the penetration is much higher which means the third statement is right coming to the fourth one this is wrong so fibrillation means how much mobile phone towers are connected by optical fiber there is an internet cable the optical fiber you use how much is connected wherein for optimum functioning of a 5g you need 60% wherein right now the major challenge for India is only 30% of the towers are fibrized you compare it with other countries in fact to be more precise it's around 33% if you won't write the exact data as per the government estimate somewhere around 33% of the towers are fibrized in India which means it is not using the coaxial cable or copper cable but instead it's using optical fiber cable but if you see other countries let's take South Korea for example let us somewhere around 70% fibrillation and if you take countries like USA 85 to 90% which means 90% of their towers are using optical fiber network wherein this is the major challenge ahead for India coming to the next one which means one is correct second is wrong third is correct fourth is wrong two statements are correct answer is b is it clear people attending online do you have any doubts on this explain second statement second statement 5g will have lower latency see a latency means let's say i'm sending a query that is uh www.google.com now from my phone this has to travel to the server and then from server it has to fetch a result let's say in google i'm searching shankarae's academy when you press the enter button you have a short lag correct so after a lag you're getting the data back so similar to that then you send the www.shankarae.in you're sending it it's like the uplink and then it goes to the server and then it fetches the data back this is called as the downlink so what is the time required for uplink and downlink together that is called as latency or otherwise called as ping on very simple terms the time gap between sending and receiving a data wherein it is lower for 5g no doubt compared to 4g it's lower but it's not as low as the optical fiber internet is it clear sandeep and dharni priyamam yeah coming to the next question 20th question many of you have answered c few of you have answered b right now more answers pouring in for option a okay all right the first one india is trying to achieve 20 percent ethanol blending in petrol that's true but not 10 percent ethanol blending in diesel we are not planning to blend ethanol in diesel we are only planning to mix biodiesel and diesel and that too somewhere around five percent five percent biodiesel according to the revised national policy on biofuel we are going to mix five percent biofuel in the normal biodiesel and the normal diesel and that to the target is 2030 for diesel we are again blending biodiesel we are not blending ethanol here petrol does not require you know anti-nocking properties and all then inherently does not anti-nocking property so and also the compression ratio is higher because of that first one is wrong if the statement was like this india is planning to achieve 20 percent ethanol blending in petrol by 2025 then it would have been correct here 10 percent ethanol blending in diesel it's wrong first one is wrong second one petrol with low research octane number is preferred for powerful engines with high compression ratio this is wrong research octane number or in other words whenever you go to the fuel pumps you have normal petrol and then a premium petrol if you go to indian oil they have something called as x95 which means the research octane number is 95 when you go to BP they have something called a speed petrol or superpower petrol something like that they are more additives and then it reduces knocking so higher the say research octane number better it is for the engine now especially for super cars or super bikes for example they always prefer or they advise generally to put a fuel with higher octane number this one is wrong third one ethanol blended petrol has higher research octane number than normal petrol this is true well there are many concerns related to ethanol blending wherein when you add more ethanol inside the research octane number increases which means the anti-nocking property anti-nocking property of the petrol also increases to understand what exactly is anti-nocking so if you understand the general working of engine so when the piston is moving up in this one you leave this part now see only the normal combustion the first phase is air and fuel mixture goes inside now after the air and fuel mixture goes inside the piston moves up what happens both the air and fuel mixture gets compressed and then the spark plug generally the spark plug it gives the spark so that the compressed air and fuel mixture will burn first step is air and fuel goes inside valves close the engine gets compressed and then the spark plug will ignite the air and fuel mixture this is a normal combustion but if you have a high compression ratio what could happen is the air and fuel comes inside but before the spark plug ignites because of the higher compression and because of the high speed engines this can undergo automatic combustion because petrols have auto ignition temperatures so which means you are going to quickly compress it before the spark plug gives the spark the engine can undergo combustion or the fuel can undergo combustion now what is the problem related to this first one unnecessary vibration will be there and then longevity of the engine is reduced because ideally only when the fuel is completely compressed spark plug functions as the igniter wherein if it is automatically going to ignite it can lead to reduction in longevity of the engine it can lead to engine damages also so this is applicable especially for high powered engines let's say you have a car which exceeds say a sedan car that's more than 2000 cc or around 2000 cc or a suv that's around 3000 or 4000 cc then this is required now if you add ethanol or if you have higher research octane number this phenomenon will be reduced basically your super fuels or your power patrols or x95 patrols it has higher research octane number and it reduces not clear so this and this is wrong this is correct answer is 3 answer is c 20th question answer is c do you have any doubts till this people are running online okay we have completed 20 questions we have 10 more questions from different fields can we go to the next one all right 20 first question okay answers are between b and d okay first one statement about one i'm sorry this option is not visible it is one two and three basically all the above the option says all the above first one trans fats or type of saturated fatty acid this is wrong trans fats are type of unsaturated fatty acids so to understand this first let's classify fatty acids the components of fats remember fats are broken down into fatty acids or other words you can say fatty acid forms fat now fatty acids are broadly classified into two types first one is saturated fatty acid the other one is unsaturated fatty acid so here saturation means it talks about the bond formed in carbon so carbon has a valence of four which means in saturated fatty acid this is carbon hydrogen will be here hydrogen will be here where it forms single bond or in other simple words you can write every carbon in saturated fatty acid will be binded to two hydrogen atoms repeat every carbon in saturated fatty acid will be binded to two hydrogen atoms where an unsaturated means if there is a carbon and if it has a double bond what will happen it will be binded only to single hydrogen atom this is called as unsaturated on other words if carbon has double bond or if some of the carbon is attached to single hydrogen you call it as unsaturated wherein this is better for health because this will react with your body and saturated is not good for health you can write it's a bad fatty acid wherein saturated unsaturated is good so depending on how many carbon double bonds are there you can further subdivide it into two types one is called as mofa mono unsaturated fatty acid that contains one carbon double bond and then you have poofa polyunsaturated fatty acid it contains more than one carbon double bond it can be two carbon double bond or C carbon double bond or multiple carbons can have double bond wherein this is the most preferred fatty acid polyunsaturated fatty acid is very good for health compared to the more unsaturated fatty acid is good for health compared to the saturated fatty acids are bad for health this is not preferred wherein this is preferred one now coming to the next one we have mentioned here trans fat so trans fat is a type of unsaturated fatty acid and repeat trans fat is the type of unsaturated fatty acid wherein generally it's produced in industrial processes so generally there are two sources where you can find a trans fat give me a minute I think whatever we wrote here it it is volatile it's disappeared but anyway you have written already now when we talk about trans fat there are two types one is naturally occurring trans fat and then you have industrially produced trans fat when you talk about naturally occurring trans fat it's often found in red meats such as beef or mutton red meats like beef or mutton they will have small amount of naturally occurring trans fat wherein if you take this may not be beneficial to health but at the same time it's not much injurious to health also because it is naturally found when if you take industrially produced trans fat first reason is hydrogenation that is adding hydrogen to the cooking oil that's called as hydrogenation of oil the main reason the industries do this is to increase the shelf life when you make a chips or any other food and if you're going to hydrogenate it it's going to have more shelf life now when hydrogen is added to the unsaturated fatty acid it turns into trans fat which is very bad for health because it will clog the arteries right now we are trying to eliminate the trans fat please go through a program called as Replace by the World Health Organization India is also having many initiatives to eliminate trans fat acid now based on this first statement is wrong because trans fat is not saturated it's a type of unsaturated fatty acid first one is wrong second one adding dihydrogen to cooking oil increases the health benefits no just now we discussed hydrogenation of oil is bad for health because it turns normal fats into trans fats this is wrong the second half is true it increases increases the shelf life that's true but there is no health benefit in fact it it has counterproductive effect on the health second one is wrong third one low density lipoprotein and high density lipoprotein are lipids that control blood cholesterol no these two are not lipids fat is a lipid cholesterol is a lipid wherein low density lipoproteins they are combination of lipids and proteins they do not fall under lipids they're a special case of or special type of biomolecule that's a composite mix of both lipid and protein now LDL and HDL are lipids that control blood cholesterol level if you eliminate this word LDL and HDL control blood cholesterol level that's true but this statement becomes wrong because it's not a type of lipid it's a lipoprotein or lipoprotein answer here they have asked which is incorrect answer is B all the statements are incorrect if you have in case if you have missed the term incorrect here generally UPSC will give the term incorrect and they'll put just a italic font for that most of the times we will miss it so make sure you see if they're telling or they're asking for a correct or incorrect statement here answer is D but in the function of LDL and HDL first we'll talk about LDL low density lipoprotein familiarly called as the bad cholesterol that's because generally low density lipoprotein it dissolves fat lipids from the liver and then it takes it through the artery if you ask if LDL is not required it is required because for cellular mechanisms or if the cell requires fat then that is transported by LDL from liver to different parts of the body but if it is elevated if there's too much of LDL more than what cell is required you call it as a blood cholesterol so when you take a lipid profile test and if your lipid profile test says there's more amount of LDL than required it means it's a blood cholesterol LDL is bad cholesterol wherein HDL means it performs just the opposite role this is familiarly called as the good cholesterol so what happens here is the blood cholesterol will be converted into cholesterol and it will be deposited on the liver so that liver the liver will excrete it so two things to remember here LDL it takes cholesterol from liver to the body wherein HDL it deposits fat or cholesterol from the blood to the liver which means LDL and HDL control the blood cholesterol level but they are not lipids answer is D 1 2 3 and all the three are incorrect can you go to the next one yeah related to diabetes three statements are given here all right first statement type 1 diabetes it's a autoimmune disorder this is true that's because the body cells starts attacking the beta cells in pancreas and because of that if a person is having type 1 diabetes which is familiarly called as the teen diabetes because it's not it is lifestyle disorder and along with it it's also genetic which means generally type 1 diabetes it the onset is at very early age sometimes for children itself they may have type 1 diabetes wherein the body will not produce insulin at all that's because insulin is created by beta cells or produced by beta cells which are present in pancreas now since insulin is not produced here it is autoimmune disorder because a cell is destroyed insulin is totally not available in the blood type 1 diabetes is autoimmune disorder when type 2 diabetes is a metabolic disorder which means the pancreas will be creating or the pancreas will be secreting insulin but the body becomes insensitive to insulin which means if someone is having high blood sugar level due to lifestyle let's say because of belly fat or because of sedentary lifestyle it doesn't mean the pancreas is not secreting insulin it is secreting insulin but the body is not absorbing it or the body is not sensitive to insulin which means the first statement is correct type 1 is autoimmune type 2 is metabolic disorder coming to the second one type 1 and type 2 diabetes have same management practices this is wrong that's because for the people affected by type 1 diabetes insulin is totally not present in their body system which means the management practice for type 1 diabetes is taking insulin from external source it's called as insulin dependent diabetes type 1 diabetes it's called as insulin dependent diabetes but in case of type 2 they will generally prescribe medicines so that the body becomes more sensitive to insulin which means type 2 is called as insulin resistant diabetes type 1 is insulin dependent which means insulin has to be delivered from external source wherein type 2 is insulin resistant diabetes insulin is present in the body but the body is not sensitive to it to it which means second statement is wrong third one type 1 diabetes is caused by deficiency of anti-diuretic hormone this is wrong the third statement is wrong that's because the type of diabetes caused by anti-diuretic hormone is called as diabetes insipidus diabetes insipidus should not be confused with diabetes meditus so what happens here is the anti-diuretic hormone it is secreted by pituitary gland this helps to maintain fluid balance in the body I repeat anti-diuretic hormone it instructs the kidney and also it helps to maintain fluid balance in the body let's say anti-diuretic hormone is not secreted by pituitary which means there will be excessive urination leading to the weight loss and everything so the symptoms may be similar to diabetes but the treatment is totally different which means type 1 diabetes is not caused by deficiency it's caused by absence of insulin not caused by anti-diuretic hormone so that is wrong well type 2 diabetes is caused by deficiency of insulin again that's also wrong because type 2 is caused by insulin resistance so the third statement is wrong second statement is wrong first one is correct they're asking which is correct answer is b 1 only generally people will be confused between insipidus and melitis so keep in mind first one you want you can quickly write diabetes first we are talking about melitis which has two types first is type 1 other one is wherein you have insipidus there's only one type wherein the reason here insulin is absent it's autoimmune disorder here insulin is present but it is resistant in this case anti-diuretic hormone is deficient or absent so that's how you classify diabetes wherein this is autoimmune disorder this is lifestyle this is this is generally genetic this is clear the government like i told you anti-diuretic hormone is related to fluid balance which means the blood composition of different fluids in the blood and also the water composition in the body it's maintained by adh please go through the endocrine system in your ncati it's a very lengthy topic but anyway it helps to maintain fluid balance we can write fluid balance so pituitary is called as the master gland that's because there are many things secreted by pituitary one such hormone is anti-diuretic hormone keep in mind it maintains the water balance one such function of adh is maintaining water balance answer is b do you have any doubts till this online is it clear okay 20 third one all right first one world's first plasmid dna based vaccine for corona virus was developed by india this is true the name of the vaccine is called zycovd the world's first plasmid dna based vaccine was developed by india it's very important because it's part of mission kovic suraksha developed by or developed in association with the department of biotech first one is true dna based vaccine for kovid developed by india can be administered in humans including children and adults 12 years and above this is true that's the specialty of the vaccine for the first time india developed a plasmid dna vaccine because other vaccines for kovid it uses a different approach wherein the first plasmid dna vaccine for corona virus that's developed by india and that's that can be administered for even children who are about 12 years third one world's first intranasal vaccine for corona virus was developed by india this is also correct recently seen in news the in kovac developed by the bar biotech the same company that manufactures kovac which means answer is all the statements are correct starting from 2018 continuously for four five years they've asked about vaccine we are not sure if the same trend is going to be repeated again but since these are significant achievements made by india in last two years especially related to the kovid management practice i've taken this question here and by the way to understand this this is the general approach taken for vaccines either you can use a entire microbe for creating immunity which you call it as a whole microbe approach or you can use a certain part of the wax part of the microbe to trigger an immunity that's called a subunit and then you can use genetic material to trigger immunity that's called as genetic approach under the whole microbe approach here are three types inactivated live attenuated and viral vector wherein so when i put this particular slide in the youtube channel and then in telegram i will put a link to the world health organization when it extensively discusses the different mechanisms for now first thing you have to understand is inactivated vaccine where the microbe will be killed and then it will be introduced to trigger immunity co-vaccine developed by barth biotech that's an example for inactivated vaccine now coming to the live attenuated vaccine which means it will have live virus but it's in a very weak form that's called as live attenuated vaccine right now we don't have live attenuated vaccine that's active for coronavirus wherein coming to the viral vector vaccine when we talk about viral vector it works something like this wherein first you take a virus that does not affect humans in this case we take a adenovirus which is generally from chimpanzee and then on the adenovirus you're attaching the spike protein or in other words the adenovirus is going to act as a carrier for carrying the spike protein that belongs to coronavirus center part adenovirus outer part spike protein of coronavirus more like it's a mix of two organisms genetically modified one this is called as a viral vector vaccine wherein we have two viral vector vaccines and use right now that is produced in India one is the kovishield even though it's produced with the help of oxford and astrazeneca here the brand name is called as kovishield so kovishield produced by serum institute of india it's a type of viral vector vaccine wherein the incovac the nasal vaccine that's also a type of viral vector vaccine so wherein in your pre-storming discussions i would have told you it's a type of live atinvaded vaccine but understand even though the virus is attenuated it again it uses adenovirus so in the fact sheet they are particularly given it's a type of viral vector vaccine so kovishield manufactured in India is a viral vector vaccine incovac international vaccine introduced in the world for the first time that's manufactured by india is also a type of viral vector vaccine and then coming to subunit approach there is a vaccine called a corby wax which is developed by a hydrobot based company called biological e that is india's indigenous subunit to vaccine for corona virus and then followed by that for genetic approach we have the zycovd and giving only the indian initiatives here i'm not mentioning all the vaccines that are approved here because sputnik is the type of viral vector and then the phizer vaccine or the moderna vaccine they fall under messenger RNA we are not talking about all the vaccines for corona virus but we are talking only the vaccines where india is involved so kovac in barth biotech inactivated kovishield serum institute of india viral vector incovac barth biotech it's a viral vector and then corby wax by a hydrobot based company that's a subunit approach and then genetic approach we have zycovd which is a plasmid DNA vaccine clear can you go to the next one do you have any doubts till this all right as expected most of you have answered d a saying one statement is correct related to third statement or the first statement wherein the answer here is none of the statements are correct all the three are wrong in different perspectives we'll talk about it coming to the first one uh so both the three are different system otherwise called as sometimes seen in news uh by the name pradhymna system so with the air defense system is also called as the pradhymna system similar to that the advanced air defense system this is also called as ashrin system ashrin missile intercept our system so when you see the term ashrin you should relate it with the aad when when you see the term pradhymna you should relate it with the prithvi air defense system so when you take a ballistic missile let's say it is launched from the source it it takes a trajectory like this and then it falls in a particular location now when we try to intercept such ballistic missiles there are two approaches first thing is let's say this is the atmosphere I mean the karmann line that defines the atmosphere or the border of the atmosphere first approach is you can send a missile that can intercept it outside the atmosphere and destroy it that is exo atmospheric that is outside the atmosphere second approach is after it reinterests in the terminal phase or in the mid phase you can intercept it and destroy wherein keep in mind prithvi air defense system is more advanced which means prithvi air defense system is exo atmospheric in nature it can go to altitude of up to 80 kilometer even though the range is 80 kilometer it is estimated to be somewhere around 120 to 150 kilometer which means prithvi air defense system can travel outside the atmosphere it can intercept a ballistic missile and destroy it wherein if you take aashwin system or the advanced air defense system it is end atmospheric maximum altitude is up to 30 to 40 kilometer which means it is inside the atmosphere where the interception will take place so the first statement is wrong second statement bramos is a ramjet based supersonic cruise missile till this portion it's true while bramos a will be hypersonic cruise missile no the upcoming hypersonic cruise missile which is jointly developed by india and russia that's called as bramos 2 called as bramos 2 bramos 2 is going to be hypersonic missile wherein bramos a a stands for air variant this can be loaded on suki flights wherein this can have a range up to 500 kilometer and it is again a supersonic missile only thing is these are land land launched wherein these can be launched from air so the second half of the statement is wrong bramos a is a standoff missile we call it as a standoff missile and it is again a supersonic missile second statement is wrong third one is wrong because you would have heard the name called as inus wickron very familiarly in news but inus wickron are 11 this was the first aircraft carrier of india not the first indigenous aircraft carrier because inus wickron or r11 it was acquired from uk wherein the actual name of that inus wickron r11 is hercules late 1960s itself we took it from uk right now it is decommission followed by that we had two other aircraft carriers and followed by that right now the inus wickron we are using it has the code iac one that is indigenous aircraft carrier one so inus wickron and bracket iac one that is india's first indigenous aircraft carrier wherein inus wickron r11 is india's first aircraft carrier but not indigenous it was acquired from uk so far we have we have got two aircraft carriers from uk and one from russia wickron was from russia wherein the present one is inus wickron iac one repeat iac one is the indigenous one wherein r11 is from uk so which means all the three statements are wrong answer is d none of the above is it clear can you go to the next one okay coming to the 25th question d option says all the above with hidden d option says all the above most of you have answered a okay the answer for this one interestingly is d all the above we will discuss one by one first one incandescent lamps that is the normal lamps which we use the ones with filament and then cfl and led lamps all these can be used for visible light communication no doubt you can use a normal lamp you can use the led lamp but when you talk about the data rate no doubt led will have higher data rate compared to that cfl and incandescent lamps will have lesser data but still the light from any of these can be used to set up a visible light communication or vlc first one is true second one visible light communication has higher bandwidth but at the same time it has lesser coverage that's also to like i told you earlier if you take a millimeter wave it has a limited coverage wherein after millimeter wave there is microwave you have infrared and after infrared you have visible which means visible light is having very high energy high frequency and lower wavelength which means if you shine a torch light it's going to be very bright but if i shine it towards a wall it cannot penetrate through the wall that's because the wall will stop the visible light on other words visible light will be easily intercepted by a thick layer of wall or a thick layer of material only on other words you can say it's a line of sight communication in fact the previous year question related to it the wrong statement was it can be used for long distance transmission no it cannot be used for long distance transmission it can be used only for line of sight communication which means the transmitter and receiver they should be in line of sight if any object is interfering let's say if it is a glass that's a different story but if it is if you are having a cardboard or any other wall in the middle then visible light communication cannot happen so that's why it is considered to be more secure that's because it's it's restricted to a smaller geographical area or a smaller space but at the same time the range is very lesser radio wave can penetrate through wall but visible light communication cannot penetrate through walls so the second one is correct third one most of the reason why you most of the people why you have chosen this to be wrong is it says it excite them to ultraviolet light which is true if you take a cfl lamp in all your tube lights or cfl lamps you have a white color coating correct that's a that's a fluorescent coating what happens is first these electrons excite and they will emit ultraviolet light so these ultraviolet light they go and strike the layer the white color layer it is going to be bombarded by the excited electrons so this will cause them to emit light the light emitted by it is visible light but initially the light will be ultraviolet so which means you have a cfl lamp cfl lamp produces ultraviolet ultraviolet strikes on the coating the coating gets excited because of high energy and these excited coating it's going to emit visible light wherein the statement that I've given here is in cfl lamp mercury atoms are excited to radiate ultraviolet light true the mercury present inside it is excited to emit ultraviolet wherein the ultraviolet in turn excites the coating that will limit visible light which means the light produced inside the cfl lamp is actually ultraviolet but what we are receiving is visible because of the white color layer on the top all the three statements are true answer is d all the above people attending online is it clear okay coming to the 26th question coming to the first statement lithium ion batteries have high risk of exploding during the charging process than discharging process logically you can mark the statement as correct because generally the batteries will burst or they will undergo a thermal runaway whenever it is being charged so we are generally advised not to use the mobile phone while charging or not to speak on the mobile phone while charging to understand this first you have to understand how a lithium ion battery works they have a positively charged diode which you positively charged cathode and then you have a negatively charged electrode called as a anode now what is used in lithium ion cells is generally cathode will be can write lithium metal oxide given the general term but it could be lithium cobalt oxide lithium copper oxide lithium ion oxide any metal oxide is used as cathode where an anode will be because of higher energy density it will be a graphite graphite is used as anode now let us talk about the charging process that is if you are going to let us say connect your mobile phone to a charging socket what happens here is this lithium metal oxide will dissolve on other words electrons will be knocked out from the lithium metal oxide now these knocked out electrons they travel from here to here which means electrons travel from cathode to the anode during charging process and at the same time the lithium metal oxide which forms ions it will dissolve inside ions are dissolved inside now during the discharging process that is once you remove the charger from the socket the electrons that are present here it goes in this direction that is electrons travel from anode towards the cathode so when the cathode starts gaining the electrons the ions that are present here they will settle back here that is the lithium metal compounds will be formed it will deposit here in this case both oxidation and reduction happens here together it's called as redox reaction our simple words you can remember oxidation it's basically losing electrons which means when you are charging cathode is getting oxidized because it's losing electrons wherein reduction means gaining electrons so while charging this is getting oxidized this is getting reduced while discharging this is getting oxidized this is getting reduced this can happen now what happens here is when you are overcharging the lithium ion battery I repeat when you are overcharging it more and more ions will be created here now when more and more ions are created here when you overcharge it so that there's a separator here so that it blocks two different ion solution so this separate this separator will be breached or it could create small holes in the separator that's a first cause second cause is too much of ions here will release poisonous and fuming gases if the ion concentration increases beyond the limit it can release fuming gases so which can lead to increase in temperature of the battery leading to explosion the two things first ion concentration increases sometimes the separator may be breached second thing when ion concentration increases poisonous gases may be emitted which can lead to increase in temper