Hello, and welcome to the NPTEL course on an Introduction to Programming through C++. I am Amhiram Ranade, today we are going to continue our discussion of medium size programs and we are going to write a program which will be a graphical editor and solver for circuits. So I should point out, I should observe that computers are often used for designing various objects, circuits, mechanical objects, chemical plants and lots of other things. CAD, CAD or computer aided design systems employ graphical user interfaces which are often abbreviated as GUI. And you have already seen this in our IDE, there are buttons and you have to click buttons to tell the computer what you want to happen or you may also have menus. So our goal for today is to figure out how these things are actually implemented. And we will be doing a very, very preliminary, a baby computer aided design program using which will have a graphical user interface. And it will design and solve very simple circuits, but it will contain the germ of many ideas and you will be or you should be able to extend it to do more complicated things, even things which might be professionally useful. So let me just talk a little bit about the circuits that we are considering. So a circuit is made of components connected to each other at nodes. Here is an example. So in this example, these black disks, so by that I mean these things, this one, this one, this one are called nodes or we will call these nodes and components are current sources or resistors. So for example, this is a resistor, this is another resistor, this is what is called a current source. So you can have many, many other kinds of components, but as we said, this is a baby program and we are only going to consider these two components. Each component is connected between two nodes. As you can see, voltage sources, current sources are connected. So between these two nodes, we have a resistor and also a current source and between these two nodes, we have this resistor and so on. And when we say solving a circuit, what we mean is determining the voltages at the different nodes. So because current is flowing through these components, it will produce voltages or potentials at the nodes. And of course, there will be the question of how much current is flowing through each of these resistors. Or other components that may be there in the circuit. So when we say let us solve this circuit, we mean figure out what are the currents and voltages in it. So our program is going to be quite simple, very simplistic in fact and it will perform the job that I have described, but it will lack many features. The appearance will be functionally adequate, but it would not be elegant or beautiful. It would not draw for example, the circuit, the way you just saw it. It will be a little bit more schematic. But again, the point is to get started and the main ideas will be there and you will be able to build upon them if you wish. Yeah, so you can start with what we present and improve upon it and our goal is to illustrate the basic issues. And I also want to mention that this is going to be another example of medium size programs. So as we write it, you will get another example of how medium size programs have to be organized. So here is what we are going to do. I am immediately going to start off with a demo of our program. So I have written the program and I will show it to you and then we will see, I will lead you towards its design. So in the demo, we will actually use the program to design a very simple circuit and we will also use the program to solve the circuit that we design and then we will talk about the design of the program. So the program will consist of a main loop and then it will have some data structures and we will discuss how the functionality is divided between the data structures and the main program. And as I said, the organization will follow sort of the general principles that we have been talking about as far as designing medium size programs is concerned. So what have we discussed so far? So we have said that CAD or computer rated design is an important application of computers. Computer based design programs often use graphical user interfaces because these are very convenient. You see what you are doing and pictorially seeing something is very convenient and very, so it tells you exactly what is going on in a very nice way. We are going to design a baby CAD program which will be useful for designing and solving resistive circuits. In particular circuits which contain resistors and current sources. And next I am going to show you a demo of the program but before that let us take a quick break.


Good morning everyone. We've given out some maps today which you can take away with you. We're going to be doing daily measurement of maps of our progress. The main issue we've got is we've still got extensive fire on the northern batters and also on the southern batter out towards the Hazelwood power station. And in that we're concentrating on the northern batter to minimise the smoke in the ash especially for more. We're doing that a number of ways. We've got fire services and specialists from all across Australia pretty well from CFA, MFB, the aviation fire services, ACT fire services and also Tasmania because what we're using as a strategy is to use compressed air foam to suppress the ash and the smoke as best we can from the northern batters. And then after that we secure it with our large aerial appliances which can put water into the coal seam if you like. Our main issue is that a lot of this is weather driven. So we've got a Tuesday afternoon when we had strong northerlies and then the southwesterly change and had the grass fire run out towards Hazelwood power station. It takes our focus off the batters and also takes the batters with the wind actually extend. So it's a bit of a frustrating thing for us at the moment where we contain something and then a couple of days later the wind takes it to a direction we don't want to go and then we come back to contain it again. So we need good weather and we need good resources to put this out. We've been working closely with the mine and the mine have put a reticulated water system on the batters for us and we've got some spray systems working on the northern batter. You'll see hopefully in the next couple of days some of that red and orange on our maps go to green. And as we do that again smoke lessons and also the fire threat. The balancing act for us is we've got the safety of our firefighters with carbon and oxide in the mine itself. So we have two hour rotations with them and also we monitor their health in the mine. Yesterday we had numerous hours out of the mine because the weather conditions we just couldn't operate. So we get behind the APOR because we can't actually fight the fire. Secondly we make sure we can minimise the smoke for more and the La Trove Valley and that's been our main target if you like. And then we've also got some other issues in the mine itself. We're balancing water issues because we're putting a lot of water into the mine and we're not taking a lot of water out and so we actually have to put a lot of water out of the mine in the next few days to give us that balance effect. If you have more water in the mine actually the integrity of the mine and some of the infrastructure in the mine becomes fragile. So that's a balancing act we've got as well. And of course lastly it's about for us is the weather. We've got some strong easterly winds tomorrow which will take the smoke away from all but it'll put pressure on the west end of our northern batter so we're working hard on that today. And then next Tuesday and next Friday is going to be some high wind days. Tuesday is going to be like last Tuesday strong northerly with the south west change and then hot and windy on next Friday which again we know that's coming and we put strategies in place to fix it. But the main thing is we're trying our best to put the fire out as fire services across the nation pretty well working closely with the mine and I know it's frustrating but it's a big job and if you look at the maps how large it is and we're taking it one piece at a time until we finish. Thank you.


Full match highlights step into our set it off early in this one Inocuous back fast from Zach your wilts on the normal circumstances, but there was no normal circumstance here They mean hide with a swing and a miss and he must rule That when the highlight reel is played Tivoli gardens get in the go-ahead goal courtesy of Zach your wilt Perhaps not necessarily against the run-up play they have the right to start the Tivoli gardens As evidenced by attempts like this this one from Anthony Nelson to the side netting And again Nathan Thomas with a brilliant pass to Horatio Morgan trying to get it to Nelson his first touch Didn't set him up well enough and a good defensive work as well also brought some Hell for them to hole in here's where the game would have turned for them a shove in the back By Nikolai Fuller on Seriki Burton Didn't need to do that did the youngster and Riccardo Thomas look where the ball ended firm in the back post and The supporters for Dumby hole in rejoicing here's where Tivoli gardens almost went ahead Shaquille Jones with a header That Damian height had to pull out all the stops stops literally and Shell shot there Tim in height forced to make a save With his leg there of the impenical you'd have expected him to at least bring that one on target unable to do so And this shot from Shaquille Paul flushed wide Nicholas Clark was happy to see it go out of touch and That's where the game ended Full time one all between Tivoli gardens and done beholden here's a full-time highlight statistics rather To on target from nine attempts from Tivoli one from four from done beholden 37 fouls on the three yellow cards to Tivoli one foot done beholden no red cards one off side for Tivoli 11 corners six particularly two saves made by done beholden and a Damian height in particular They have the line two possession 61 in a match that overall lacked quality and perhaps a Fear result in the end of one all between Tivoli guns and done beholden The man of the match is standing with Chris Taylor. Let's hear what he has to say Ricardo another matter of the match performance for you not an easy battle against Tivoli guns But how important is it even to come away with a point? I think we did want to cheap points, but we are grateful for the pint on the road We are very grateful for the point tough for you as well because you're without your leading goal scorer Nicholas Nelson So you have to step up to the spot. We know it's always a ruffle whether you're going to take it with the right or the left How did you decide which one today? It's all come from a chain ago being practicing my board foot and I feel comfortable the right foot today. So kick it in my right foot today Still solid in six position. Do you think you can maintain that for the rest of this season and get into those players? I think we want more but we're going to maintain that portion and try to reach further Of course you played with what I was before you went to the top of the preliminary round at one stage Do you think this don't beholding team has what it takes to go all the way? Yeah, I think we have the quality. I think I'm we have a great coaching staff managing staff to reach there So we'll take it a step One step at a time good promise today Ricardo and look to more bit to more good performances from you throughout the season Thank you Ricardo Thomas their own man of the match today The captain of don't beholding in this one or draw with Tivoli guns always a tough match as well


We now have a presentation of a proclamation for Muslim American appreciation and awareness month I would like to invite Munir Safi and Humira Nawaz with the Muslim Community Center the East Bay to the lectern while I read the proclamation Recognizing August as Muslim American Appreciation and awareness month and then after I read the proclamation You are welcome to offer comments and if you'd like take a photograph with the council. Thank you Whereas enriched by the diversity of its residents the city of Pleasanton takes pride in supporting individual religious freedoms for all and is strengthened by the Contributions made by the many diverse religious and cultural traditions of its residents including those who practice Islam and whereas Alameda County is home to over 90,000 Muslims who make innumerable Contributions to the cultural political and economic fabric and well-being of our city county state and nation and whereas Mosques and local Muslim organizations such as the Muslim Community Center of the East Bay and the Islamic Center of Zahra Stepped in to help the entire community during the pandemic by donating funds distributing food and Sewing masks for front-line workers as well as educating their congregations about social distancing guidelines to keep the community safe And whereas though the Islamic practice of zakat Local Muslim organizations help help give back to the community by providing grocery deliveries and financial assistance to local families organizing quarterly blood drives food drives and backpack drives for schoolchildren as well as many other charitable activities serving individuals and families throughout the community and Now therefore it be it resolved the Pleasanton City Council does hereby proclaim August 2022 as American Muslim appreciation and awareness month to acknowledge the rich history and contribution of American Muslims in our community and may it have a lasting positive impact for our city state and nation Thank you Good evening mayor Carla Brown city council members Thank you so much for honoring our state's designation of August being Muslim appreciation and awareness month This is the seventh year that the state of California has recognized August Muslim awareness month and the fourth year the city of Pleasanton and its city council has given this honor to us Thank you so much for making sure that your residents feel proud to be living in the city and Feeling that they're part of the rich fabric that makes pleasant and so special My name is Humira Nawaz and I'm a resident of Pleasanton for the last 25 years I have actually been an employee of city of Pleasanton for a few years as well I'm representing Muslim community center as you said which is located on Las Desitas Boulevard Which takes great pride in building bridges between the city and the local community as you Very graciously told everybody that we have been supporting through Alameda County Food Bank and through our own community funds food drives and weekly food distributions Along with many other Charities that we support the community. This is our way of giving back and saying. Thank you Muslim Americans have lived and contributed in these communities since this country's founding in very various ways Sadly in the last decade and the half the impact of Islam will be Tobias has been very real and our community has felt it We have heard from our congregation members women wearing their faith on their head in the form of a headscarf In walls and shopping centers hospitals of this Progressive bubble that we live in very of feeling intimidated which we never felt before Our students in a recent study done by Council on American Islamic Relation reports 49% of American Muslim students have experienced bullying and worse 38% of those surveyed the bullying has been done by the teacher In workforce employees and applicants who are Muslims have filed lawsuits against employers and have won them based on religious discrimination At this point, I would like to deviate a little and thank a person in this room Who made a huge impact? For me on the day 9 11 happened was the first day Gingerbread preschool was having back to parent night and my boss at that time Becky Hopkins Suborted a scarf I had walked up to her and said Becky. I don't need to be here today because Emotions are running high and I don't want to make any parents feel uncomfortable Who does dare remember she hugged me and said who met up you belong here It's people like her and experiences like these that give a hope that our children will not have to face these Discriminations and they will be able to conquer The device that we have built over the last few years Once again, thank you so much city council of pleasant and we appreciate Recognizing and giving us this honor We continue to we hope that we will continue to build birch bridges with the city of pleasant and 3.3 presentation of the American Muslim Appreciation Awareness Month Proclamation so the city council we will present the American Muslim Appreciation Awareness Month that we were going to present it earlier Last month, but I know that we wanted to make sure you guys were Included and you guys were able to visit and so We would love to present this Certificate to you and I will read a couple of the the first few sentence Whereas freedom of religion holds distinction as a cherished right and fundamental value Upon which the law and ethics of the United States are based and the city of Dublin takes great pride in supporting individual religions freedoms and strengthened by Contributions of its diverse population including those Americans who practice Islam and the earliest Muslim immigrants most mostly worked on Farms and made significant contributions to early agricultural efforts and approximately 1 million Muslim Americans currently reside in Communities throughout California the highest numbers in the United States and the citizens of the city of Dublin benefit from Muslim religion Education and empowerment organizations that operate within our city and we welcome a mod. Please come forward Good evening and Salaam alaikum I wanted to thank our esteemed city council and I'd love to be able to come here every year and thank you guys For all your support and for your recognizing Muslim community and of Dublin as an integral and welcome part of our larger Dublin community Assemblymember Bill Quirk introduced this resolution in 2016 at a time of great turbulence and uncertainty But Dublin and California have always stood for inclusion and have always been a welcome sanctuary for all We're very happy to be here in 2022 in person with the community here in person to be able to celebrate the recognition of our community Last year at this time the city of Dublin pledged itself to partner with the community of welcoming refugees from Afghanistan In this last year we were able to help hundreds of Afghans relocate to the area and find a home and community here in Dublin And the local surrounding cities Twice every month our local community hosts a bizarre for newly resettled families to receive household goods clothing Backpacks books and more for little to no cost for the Muslim community center that many from Muslims from Dublin attend Muneer Safi the director and Sabine Asif Ali our board member have worked hard in a residence here here in Dublin To constantly have an open door policy at the mosque that makes everyone feel welcome whether it's their first time or they're a regular attendee They've expanded their services to make they eat celebrations family events and regular prayer services multilingual environmentally friendly and disability certified through a partnership with the alameda county food pantry mcc's Sister ominous selflessly runs the food pantry where weekly thousands of pounds of food are given out to hundreds of families From all faiths throughout the tri-valley I was fortunate to be able to volunteer there with my sons to help deliver food on a number of occasions I would like to particularly mention Shazia Kajani and her son Zayan who are residents here of Dublin and were featured in the Dublin patch For their hard work with the refugee bazaar And for raising money to purchase laptops computers so that resettled families can have internet access for school Job hunting and pretty much everything else that we do these days So their hard work is makes us all proud to be Dubliners These stories are just the tip of the iceberg for the ways that our local Muslim community regularly invests in our Dublin community We're taught that civic service is a fundamental tenet of our faith Those who are best at creation those who are most compassionate with creation are the ones who attain An ultimate compassion mercy and closeness to the creator I wanted to highlight these efforts because it's these stories of the human spirit rising above challenges that we all need To sustain us I would also like to thank samina usman and sima brother from the council of american islamic relations who are constantly advocating for civil rights on behalf of all americans and for To particularly mention sima's efforts. She's running for the ds rd local water district And in the upcoming elections kash of kadri who'll be running for a dublin city council It's not just what's good for a few but what about what's good for everyone and most importantly about what's most In for those of us that are most in need that drives them to serve and to serve here in Dublin We're proud of their willingness to serve and look forward to celebrating their elections Muslims and muslim-run community organizations throughout the local area particularly in dublin constantly strive for the greater good There's maristan that's focused on low to no cost mental health services for our local community Along with zakat foundation and our local resident minara rahman who coordinates food distribution throughout Alameda county and Necessities for those most in need. I would also like to highlight Some international organizations that are run out by residents here in dublin I personally work on an international economic development project supported by the united nations development program Not only for its economic impact, but for the international conflict resolution promoting equity environmental sustainability And fair and livable wages for economies across the developing world Muslims in dublin have a strong and global impact that we can all be proud of However, there are many who are focused right here in dublin Samir koreshi who serves not only um to politically organize our communities And advocate for our use of our first amendment rights, but also serves as a chairperson for the dublin senior Centers advisory board and so will be a koreshi who spent many many years working on pfcs and pfso's And on the dublin partners in education And then of course I have to do that my shout out for dpi because they're doing registration right now It's open and i'm going to get a message from rich later that did you mention that so I did my shout out for dpi How much the rich pay you Like them there are many others shazia nomani shaheen parker rabia adil nidda ahmed and more Who work year after year to make dublin students their primary and central concern Participating in these efforts is essential work of being part of a community Last and far from least I want to thank alisa shahab and cave gelani who are two high school students who recently graduated from dhs Alisa was active in the dublin inclusion project And was the president of the muslim students association at dhs and was Gave a powerful speech at dhs's last graduation ceremony Cave was honored as a national merit scholar and started a nonprofit organization called youth coding workshop That organizes high school students to teach their younger counterparts How to code and they've had chapters at every middle school in the area and are expanding to elementary schools as well Their dedication to inclusion and service as young people has propelled from active service in high school to now attending esteem universities Both are an inspiration to students coming up the ranks and to those of us who have already graduated as well These students remind us to be proud of who we are to always respectfully expect To be seen for our muslim identities, but to actively serve all members of our community This is a lesson that I would like to take forward into the next year And to thank you all again for the time and recognition of our muslim community. Thank you very much What Honestly, thank you for for naming all all the individuals that you did because they are part of our community and People like samir and his wife that give up so much of their volunteer time this you know the students at dublin high school and They just want to be able to be part of the community and also show that you know being involved and Making your community even better. And so it's all about all of us patching in and I know during these difficult times You know congressman swal was there Even supervisor howber was doing funding and and bringing in families to be able to help them So I think we just live in a great area where we can all come together And it's the key role players that help but also the community And we just keep doing that over and over again because it's very contagious to keep doing positive things like that I know I want to actually give um council markum a guy A couple minutes to speak because I know that he wanted um, he also wanted to say something last time and and he's Be assumed this afternoon or evening Yeah, uh, so great to see everyone here and I'm glad we were able to do this where the community could come and I wish I could be there first and uh to see you and to be part of the photo, you know, we've been doing this now for Several years. I think it's a great tradition And I love in the in the proclamation how it says towards the end that It is it is appropriate for us to promote awareness of American Muslims in Dublin And across the nation and to extend to them the respect every American deserves And I think that's that's so important that we are reminded of that Um, there there are still there are still challenges Around perceptions and lack of awareness in our country and we should daylight that Like here in Dublin All are welcome and we make concerted efforts To ensure that our residents understand that so thank you for being here tonight and really happy that we are able to to do this I want to echo my colleagues. Thanks. Um But also a talk about, you know, we we highlighted the fact that you named an awful lot of people and the communicate the Contributions that they have made to our community And you mentioned a couple of tiny little things that you do But you glossed over your own contribution to the city of Dublin You don't just work for the food bank and for international and national foundations but you do an awful lot for the city of Dublin and certainly the Koreshi's do and Shazi no money and just so many other people and Samina and everybody else But you do a lot for the city of Dublin as well at Cottonwood Creek and with other Committees at Dublin schools and all of those things And so I just want to make sure that we are all taking a moment to thank you for your Commitment to the city of Dublin and the residents here in Dublin as well as to the greater Muslim community And the greater Tri Valley community and so that needs to be said as well So I'm I'm really pleased that you come every year and you highlight The contributions that the Muslim community as a whole makes to the city of Dublin But the the contribution that you make to the city of Dublin too does not go unnoticed by those of us that live here So thank you very much. Thank you Please come forward and we can Present the the certificate too, but also would love to take a picture Our next proclamation item 6.2 is recognizing the San Ramon Valley Islamic Center and the San Ramon American Muslim community for the contributions of American Muslims to the San Ramon community Is so be a here. I pronounced that right so be it and you brought with you your vice president. Is it is it decent? Okay, and Nadia your that was a tough one to figure out Please join me up here. We have a proclamation for you recognizing the San Ramon Valley Islamic Center and the San Ramon American Muslim community for their contribution to the San Ramon community Where as San Ramon is home to the San Ramon Valley Islamic Center with the dedicated serving and spiritual needs of San Ramon Muslim community and promoting interfaith quality by providing an environment for dialogue education and development And whereas the SRVIC have provided many volunteer services to the San Ramon community Including a non limited to the fall Partnering with the International Refugee Committee to support newly arriving refugees To the Bay Area and help with apartment setup programs That's gotta be a job itself Partying I'm sorry packing and distributing 100,000 pounds of food samples and masks at risk community in the Bay Area To them you are not alone program if partnership with sports life foundation and other Bay Area uh Fostering the SRVIC flow drop the American Red Cross Being one of the largest donors to the conflict cost of food that donated 25 to $30,000 every year In addition to the estimated 150,000 of those ancient to community members in need Maintain a section of highway 680 top bound as part of the adopt the highway program Whereas most homes have been part of the u.s. History from the beginning They have the goodness to the production of wealth and construction of the nation They are also part of the rich history of the civil rights And whereas almost 10,000 Muslims reside in the county and make a notable contribution to the cultural political and economic fabric and well-being of California and the united states Now whereas American Muslims are teachers, lawyers, doctors, social workers, sex workers, services, and business owners among numerous other value professionals as well as e-filters, activists, entrepreneurs, and politicians Now whereas the California State is going to have to recognize the month-long What's going to it? American Muslims are appreciating analogies And whereas it is appropriate to acknowledge and promote Awareness of the new medium of a people's country American Muslims in California And for us to continue to extend it down to respect and congregate every other community Now there are four big results. The city council and the city of San Ramon does hear Michael Clinton It's appreciating the efforts of the San Ramon Valley, the Long Stateness, and the American Muslim community As a contribution to the San Ramon community And for the lasting positive impact they have made Thank you I'm doing it right We want to speak to the cameras that keep going I'll let you hold this and who wants to be the first speaker I'm going to speak with you Thank you Okay, take 40 minutes In the name of Allah most beneficent and most merciful Mayor Hudson council member Thank you for honoring the American Muslims of San Ramon with the proclamation for the recognition of the American Muslim month The San Ramon Valley Islamic Center was set up more than 25 years ago And our members have been a vibrant part of this community At our center we have witnessed generation A generation of American Muslim grew up Go to school work and eventually returning here to grow their families In the past year San Ramon Valley Islamic Center helped blood drive through the American Red Cross As one of the largest donors to the Contra Costa Food Bank during our Ramadan food drive also Our team member our community members are also part of the community highway cleanup program In the last years the San Ramon Valley Islamic Center Together with other community organizations in San Ramon rallied more than a hundred thousand dollars of resources to help The displaced people from Afghanistan We the the center also received a 50,000 grand dollar grant from welcome usa towards our refugee relief effort, which and we were one of the 30 organizations across the whole united states to have received that grant So once again, we thank you for the proclamation and we wish everyone a good evening Did you want to speak now you have to introduce yourself? Well, I just want to say thank you for everything you do in the community and especially and I've been part of some of the food drives and the things we do and particularly during Ramadan when we are not eating As Muslims and being able to distribute that food so appreciate everything you've done in the community and Thank you ladies for serving on the board there Well, I also want to thank you very much for all the work you do and I I know you you do a lot in terms of particularly welcoming People from overseas and your food drives and we thank you very much You know you used to we used to be across the street from you You know our city hall was across the street and and so it was always such a good relationship there We've moved over here, but thankfully we still have a good relationship. So thank you very much for what you do Mark Yeah, thank you very much For all your contributions the sponsorships and the food drives and the In the distribution red cross support. That's all just fantastic You know faith is such an important aspect of our community and and I just want to thank you And the Muslim community for all they've done for their their contributions For our community. Thank you That's kind of gross Thank you. Thanks for all your services. If I remember right, you also provide auto Uh donations right to help the families Is it mca really because when I was looking at my used car donation So one of the things I reviewed and I felt the best place to donate is to mca So I donated my car to mca at that time. So Never much right. So yeah, so thanks. I know the services that you do is fantastic it and especially the interfaith That that plays a key role to keep Our community safe and especially this is definitely important day for me the timing What happened in albuquerque? So that's not acceptable in any community especially in our nation. So it's very sad that these things are happening and it's good that we are recognizing your contributions and You're always welcome to let us know if how we can help you and make it much better. Thank you Yeah along the same thing My neighbor used to be over would always invite me over Uh, I heard actually at one of these meetings like that. He passed away Abid Farooq in a mirror. I know is there ravina And you know, it's just it's one of those things to highlight on what you just heard from shridhar Once you become neighbors Most of the other stuff sort of fades away But then there's that moment that comes up that you know Something just that should not happen I'm amazed right now and you hit on it and I wanted to highlight this How many calls I get about visas coming out of at the can of stand That people are still trying to get out to jik stand or somewhere to get over here And I almost want to tell them why don't you just go to Mexico and walk across the border everybody else is But it's not funny. I mean the these people are trapped there and fear their lives. So I don't know what can be done. We've tried going back through Congressman, uh, we're kind of in between two congressmen right now Um, but I know it's something that just can't stop because there's still a lot of people there That want to get out and that program that you have helping these people get Uh reacquainted into our community or get acquainted into our community is much needed. So I can't thank you enough Uh, any last words you'd like to say or Or Interfaith on program with well, is he gonna give the speech or is it just gonna hide over there? You want to come up and say something? To just make sure that we're all you know here for each other. Yes I'll just say something quick. It's uh, it's an honor being part of this community and uh always come in here always feels Homely, I mean this is a good city that's open minded. It's receptive to All religions and we're really happy to be a part of it. Yes kind of the sum of it. Yes. Thank you so much And please stay with it. There's still a lot of work on those visas on to um proclamation Declaring august 2022 is muslim appreciation and awareness month Uh presented to a manure syphie of the islamic center of livermore and councilmember minnow will read the proclamation It gives me a great pleasure to present this this uh proclamation for muslim appreciation awareness month And I will read it as follows. Unfortunately, I've tried holding this up to zoom and because of the nature of zoom background Um Didn't work so well, but trust me. It's a lovely proclamation and we will be delivering it in person to uh the islamic center shortly This is what it says Whereas the city of livermore has been and continues to be home to people of different national origins immigration or refugee status cultures histories races ethnicities religious affiliations or none Gender identities sexual orientations ages education economic status and physical mental or emotional abilities Our strength is derived from our diversity and inclusiveness from respecting one another From welcoming immigrants and others and from collaborating with one another across our differences and Whereas the city council believes that a city can best stand against bigotry Intolerance and hate Through leading by example and living our shared community values of welcome inclusion and respect And by developing common ground In venues that allow us to talk and work together in service to each other and our community And whereas muslims have been part of the us history from its beginning And have contributed to the production of wealth and the construction of the nation They are also part of the rich history of the civil rights movement Over 90 000 muslims live in alameda county and make innumerable contributions to the cultural political and economic fabric And well-being of our state and our country and Whereas the covet 19 pandemic forced the temporary closure of the islamic center of livermore And other mosques in the tri valley During this time these mosques and community organizations provided online programming And service service sermons with small faith group prayers outside They also answered the call for help by donating funds distributing food and by sewing masks to help those on the front line And they have educated their congregations about social distancing guidelines and practices to keep the community safe Now therefore the city council of the city of livermore proclaims august 2022 as muslim appreciation and awareness month And thanks the members of the islamic center of livermore for their contribution to the city And encourages members of the community to come together to celebrate our diversity That's on behalf of the city council of livermore and the actual proclamation. I'm going to see if I actually can hold it up here Oh, no, if that really doesn't work That will be delivered to uh to the islamic center Um tomorrow or the next day. Thank you so much Hello council Yeah, yes, thank you so much for allowing me to speak. This is minir safi with the muslim community center Uh, good evening mayor and council. Thank you so much for honoring our state's designation of august being muslim appreciation and awareness month Uh, this is the seventh year this designation has happened in california And this is the second year this happened in livermore I can tell you the hundreds of muslim families in livermore and the nearly 15 000 muslims in the tri valley We truly appreciate the livermore city council presenting this proclamation today Uh, so i'm representing the pleasant in muslim community center. We Serve the entire tri valley we're a vibrant regional mosque and we've been on In pleasant for the past 11 years And i'm also joined by colleagues in congregation from the islamic center of livermore They're all they were watching online and probably you're still watching Uh, I just want to quickly say american muslims We've lived and contributed to our community since our country's founding in the last decade and a half The impact of uh islamophobia has been real but despite this we continue to do our blood drives our voting drives Our highway cleanups our weekly food distributions We have an open door policy at our friday services. We serve as a red cross disaster site Host esl classes interfaith events open houses Uh, we're a green mosque special needs friendly mosque So you can hear we're just part and parcel of our community and I can tell you that this recognition Makes a world of difference for your livermore constituents who are muslim So again on behalf of livermore residents center muslim and tri valley residents who are muslim We thank you so much for this proclamation proclamation and this recognition. Thank you Well, thank you for all your do it and thank you, uh, else merman roe for uh, Recognizing that he was still in the audience. So thank you very much


Hi, I'm Zor. Welcome to Unisor Education. Today I would like to talk about magnetic field. Now this lecture is part of the course Physics for Teens presented on Unisor.com. I suggest you to watch this lecture from the website Unisor.com rather than from, let's say, YouTube where you might have found it through a search engine because the lecture is part of the course. So there is a hierarchy of different topics presented on the website. You can just go sequentially or in whatever order you prefer. Every lecture has detailed notes right next to it, which basically is like a textbook. You can use it. Plus many topics have exams, so you can basically check how you know the material. And the site is absolutely free. There are no advertisements, no financial strings attached, and you don't even have to log in if you don't want to. Okay, so magnetic fields. Well, first of all, we have the fact that magnetic force exists and it acts on a distance. Now, I'm sure you have problems with the concept of acting on a distance. The force which acts without really touching each other. I mean, I have problems. Physicists have problems and they have come up with a model. Basically, it's a word which describes the whole thing. It's a field. So it's a force field. Well, introduction of the word doesn't really make it much easier to understand, but well, we deal with this. We live with this. So we know that there is such a concept as a field. We consider this field as a reality and we study it as much as we can. So there is such a thing as magnetic field. And we have to study it, right? Now, before the fields we were studying before were gravitational field and electrostatic fields. They are easier. And here is why. In both cases, in case of gravitation and in case of electrostatic, we actually had absolutely no problem to assume the simplest object, which had the property of the source of the field. It's a point object with certain mass for gravity. It's a point object with certain electrical charge, with certain excess of electrons. Well, there are no point objects, obviously, but you can imagine a very small one. And it has certain number of excess electrons or deficiency of electrons, and that what makes it charged. So geometrically speaking, it's a very simple thing. It's a point. We're talking about mathematical abstraction, obviously, in this particular case. So it's a point and it's easy. And if you would like to have some kind of a more complicated object, we can always break it into small pieces, each one small enough to resemble a point, and basically integrate the fields, which are produced by every part of it, every particles of it. Now, in case of magnets, the situation is significantly more difficult. And the primary reason for this difficulty is that magnets have two poles, which act against each other, so to speak. So if this is the magnet, let's say this is the north, this is the south poles, you can't make it a point. You cannot make it small enough. The most reasonable thing to assume that this is a rod, a thin rod, and still it has certain finite, not infinitesimal, finite lengths, and one part is north and another part is south. You cannot avoid that. Now, that's not the only complication. Another complication is that the force which is produced by the north pole, not only it's opposite to the south pole, but the problem is that everything in between, every point in between, also is a source of some kind of a field. And the source is the weakest in the middle, actually it's zero. There is no magnetizing in the middle of that thing. And it's the maximum on this side and on this side, and then it's diminishing down to zero and then increases again, but in a different direction, it's like positive and negative. Complicated. And to study it, I mean, let's say you would like to know what's my field at that particular point. Well, the field in this particular point is a combination of all the fields produced by each one of these guys. And again, what's the length of it? I mean, how can we establish a probe object? A probe object is supposed to be a magnet as well. So it's supposed to be some kind of a rod, if you wish, or a bar magnet or a very small bar magnet, but still bar with a finite length. And now we have also an angle, not only the distance, but also an angle. Complicated. So what can we do about it? Well, we will try. The first thing which we will probably try to do is to establish how this magnetic field around the bar magnet, well, bar magnet is probably the simplest, but it's still complicated. But in any case, if this is the simplest, let's just try to find out how the field around the bar magnet actually looks like. So if you have a bar magnet, let's say horizontal. This is north, this is south. How can we visualize the forces which are actually around this magnet? Here's how. And this is the experiment which we can do at home, if you wish. I'll just explain it. So what you need is, you need iron shavings. You know, when you're just working with iron, you're polishing or whatever, there are some shavings. So you need these shavings. Now, if you will drop these shavings on the table, let's say, where the magnet is located, they will somehow organize into whatever the figures are. And the figures will be something like this. These are little shavings. So what happens is, you know about temporary magnetism, right? So iron shavings, these pieces of iron, are really tiny temporary magnets. As soon as they are in the field, they are magnetized.  Well, temporarily, while they are in the field. Now, as soon as it happens, all the north poles are connected to south poles or south poles to north poles. And they are actually connecting into these lines. You will see these lines. And in the notes accompanying this lecture on the website, I actually have a picture of this. Well, I took it from internet, obviously. I didn't do experiments myself. But yes, experiments are done in different circumstances, in different environments, etc. That's what's going on. So you will see that these are the lines along which these shavings actually are positioned. Now, if you remember in gravitation fields and electrostatic fields, we do have a certain concept which we were talking about, equipotential surface. If you have a point object as a source of electrostatic field, equipotential problems are spheres on different radiuses. These are equipotential surfaces around the magnet. Now, so it looks like there is some kind of a force which is directed from north to south. And the force is, by definition, chosen north to south. Why north to south, not south to north? There is no why, just by definition. It's a tradition. Same thing as in electricity, when you have a direct current, you, by definition, say that this is from positive to negative. Why? Because probably people have decided that this way, somehow in the very beginning of the studying of electricity, and at that time they didn't even know about electrons. So they didn't know that it's actually electrons which are traveling. They said, okay, let's just define that the direction is from plus to minus. Here is the direction from north to south, so that's it. Now, which is north and which is south, by the way? If you would like to determine, well, considering the earth is a big magnet and the north, by definition, is where the north pole is, more or less, then you just position your magnet in such a way that it will orient itself along the meridian, and whatever the end points to the north is called the north. In theory, it means that the earth as a magnet is actually, if you will consider earth to be like a bar magnet along its axis of rotation. The south pole is on the north, right? Otherwise our north compass wouldn't really point to it. South and north are attracting each other. So this is a little deviation. So this is my earth, this is my north pole. And we are talking about north's magnetic pole.  So this is supposed to be a south pole of the giant magnet. I mean, whatever it is, we just call it a north magnetic pole just because it's on the north, but from the magnetic lingo it's a south pole of this giant magnet. And our compass actually points with the north towards the north's magnetic pole which is actually south, but it doesn't really matter. I don't want to confuse you too much. In any case, it doesn't really matter what is north and what is south. What there is, there are two of them. And that would complicate the whole picture. Now, before I am going any further, let me check. Okay, basically everything before the main thing of this lecture starts, I have covered. So whatever I was just saying, it was a preliminary thing. Now, what's important is we have to understand why magnetic field actually exists and what makes it, basically, whatever it is. Now, we know that about electrostatic fields, for instance, we know that the source of electrostatic field are electrons. So there is some kind of a material object which is the source of electrostatic field. Well, we don't know how it does it, but it does it. At least there is something which we can hook to this electrostatic field, an electron. Now, in case of gravitation, we always talk about the mass. Any piece of mass actually, any object which has certain mass has this qualities of being the source of gravitational field. What is the source of magnetic field? So that's what I am talking about right now. And this is the main part of this lecture. So let me wipe out this and talk about something else. In many cases, physicists are coming up with a model which kind of describes whatever they want to describe to a certain degree of precision. And if it corresponds to whatever observations they make, well, they say, okay, that's a good model. Maybe the universe is really done this way. Well, maybe not, but chances are that it's a good model and we can use it if it corresponds to everything whatever we know about the universe. Then maybe we can use this model to predict certain qualities of the universe for whatever we don't know yet. So let's just develop this model further and further. Well, that's how models are created. That's how they are coming to a dead end if they find something which cannot be explained within the model. And then they try to build another model, more sophisticated, whatever. So I'm talking about a model right now. That's what I suggest you to use to kind of better understand how a magnetic field works. Now, whatever I'm saying right now, or will say right now, is it really how a universe is built? I have no idea. However, it's a reasonable model. It explains whatever we know about magnets. And I think at least at this particular point in your education you might be satisfied with this model. So here is, let me start from a slightly different concept, but it will basically eventually lead us to the theory behind magnetic field. Now, consider you have a particle which is rotating, this is my particle. It's rotating around the axis in certain field, in certain plane. Well, plane is perpendicular to the axis. So it's rotating. It has certain radius. It has certain speed of rotation, angular speed, whatever it is. Okay, fine. Now, let's imagine that on the same axis in a different plane, so this is my plane. Now, in a different plane, there is another particle which is rotating, let's say this is the direction. Maybe a different radius than this one, maybe with a different speed, along the same axis, and the plane is parallel. Okay. While these two planes are relatively far from each other, well, particles don't interact. But let's try to make them closer and closer together. Well, here is a very interesting point which I think makes sense just intuitively. If they are rotating in the same direction, which means that, let's say, we're positioning our observer here. So this observer looks at this particular thing and it's counterclockwise. And look at this one, and it's also counterclockwise. So it's the same direction. Now, what happens when we are making these two planes closer and closer? Well, these two particles don't really disturb each other. If there is something around them, some kind of a force around them, whatever the force, gravitational force, whatever we know about, electrostatic force, they probably don't really bother each other much. If they are spinning in a different direction, so this is this way and this is this way, they disturb each other. So one particle would probably somehow prevent another particle of moving, especially if their radiuses are relatively close to each other. So there is a very reasonable assumption that if they are close to each other, if they are spinning in the same direction, then there is something which might actually even attract them to each other. So they will join these two planes. But if the direction is different, opposite direction, then there is actually some kind of a resistance from making these two planes closer. And we can talk about repelling. So this is my model, this is a starting model. So I assume that these two particles will bring the planes closer and attract each other if they are spinning in the same direction and will repel each other if they are spinning in different directions, in opposite directions. Is it reasonable? Well, I think it is reasonable, especially considering that around each particle you might have an electrostatic field. Fields somehow interact with the field of this guy and when they are going in the same direction, that's okay. I mean, that's probably fine. But if they are going in the opposite direction, they repel. Well, if this seems to be reasonable to you, let's go one step further. Let's consider that this is an electron. An electron is rotating around the nucleus within the atom and maybe we can think about certain plane where it is actually rotating around the nucleus. Now, this is another atom, another electron, rotating around its own nucleus. Now, let's forget about the plane, this is the common axis of them. Even if it's not common axis, but if they are in the same parallel planes, it still kind of makes it easier to align to each other. So, my point is that if all these atoms are aligned in parallel planes and all are rotating in the same direction, then they actually, each particular atom behaves like a bar magnet with north and south pole here, north and south. And in this particular case, this attraction is really equivalent to the attraction of two bar magnets positioned exactly like this. North to south will be attractive. Now, if, however, my direction is opposite, so instead of this, I will have this. Well, if you will look from another side, it will be south-north, right? We just turn the whole plane upside down. So, the whole, assuming inside there is some kind of a bar magnet because behavior is exactly the same. So, we are turning the whole thing upside down so the poles are changing and now there is a repelling south to south or north to north, whatever it is. So, my point is that if you assume that the model of this spinning particle is reasonable, we can actually make the next step and basically take a look at what's inside the object. Inside there are atoms. Atoms have electrons. Electrons are rotating in certain plane within each atom and if they are properly aligned, it makes the whole thing like a big magnet actually because they are all pointing in the same direction all fields are coming together. So, let me go back to north-south model. So, even if you assume that these two are basically nullifying each other there is no field because they are already touching each other. It's like plus and minus in electrostatic. But still the surface has this property of all these are acting as north pole, right? And all these are acting as south pole. So, this is an object itself. So, the whole object becomes a magnet. Now, if, however, all these atoms are randomly directed and all these electrons are rotating in different non-parallel and not aligned properly planes, then all these north poles and south poles they are randomly distributed inside the object and they nullify each other and there is no external magnetism produced by this particular object. So, my point is that according to this model whether it's true or not, but it explains basically all these properties which we are observing with the magnets. So, just keep it in mind. The model where electrons are rotating around certain axis within certain plane in each atom and if these planes of rotation are properly aligned we do have a magnet. Now, we have permanent magnets and we have temporary magnets, right? So, permanent magnets is basically when it's permanent. Now, the temporary magnet is, let's say, a nail. You have a soft metal, like a soft iron, a nail. If you position it closer to the magnet then the magnetic field of existing magnet will align. So, if these are really very easy to align, they are very flexible, so to speak, then all these north things are aligned if this is a real magnet, a permanent magnet. Now, this is a north pole and this is a south pole. Let's say a horse-shoe magnet, a giant horse-shoe magnet, north and south. So, if these are really flexible, they are aligned and as soon as they are aligned they become a magnet. If you take it away, since they are so flexible after a certain time they will rearrange themselves randomly again and it will lose the magnetic properties. But while there is this field outside, this thing actually orients all these axes, parallel to each other, planes are parallel to each other, and that will be a magnet too. That's the temporary magnetism. And finally, if they are randomly arranged but not flexible then this is a diamagnetic thing which means it cannot be magnetized, like plastic, for instance. It can magnetize the plastic. Okay, basically that's all I wanted to talk about today. Again, this is a model. It's our view which, well, seems to make sense and it seems to explain certain things. And, well, if it explains whatever we observe then, well, let's just use this model. Now, what's very important is that before this lecture everything related to magnetism was basically about magnets. It was not related to electricity. Now, this model actually established a very, very tight relationship between electricity and magnetism because magnetism is produced actually by electrons as well as electrostatic field is produced by electrons. Electrostatic field produced by existence of the electrons. Magnetic field is produced by their movement. So, we have a static and dynamic in mechanics, for instance. We were using the statics and dynamics. One thing is just about positioning and other is about movement. Electrostatic is the same for electromagnetism as a unified theory. So, electrostatic for electromagnetism is what's static for electricity. And magnetism for electromagnetism is both dynamics for mechanics. They're kind of parallel to each other. So, again, electrons and their movement. These are the major sources of electrostatic field and magnetic field. And basically, we will talk about one concept which is called electromagnetic field. And that's why the whole subject which we are talking about is called electromagnetism because they are together. This common source, the electrons is extremely important for understanding all the properties of electricity and all the properties of magnetism. Okay, that's it. We have established the connection. And this connection is extremely important. And in the next lecture we will always talk about electricity and magnetism together in some way or another. I do suggest you to read all the text which is accompanying this lecture on Unisor.com. There are a couple of pictures, much better than I draw. And just, again, try to familiarize yourself with the model. Model explains the source of magnetism and, again, without staging that this is exactly how the universe is built, we do know that the model is relatively sufficient to understand whatever is happening, at least at this particular level of your knowledge about electromagnetism. There are much more complex issues and the theory, the real theory, which is right now, let's say, it's a current physicist's view to electromagnetism, is significantly more complex than whatever I was just explaining. However, it's a good first step. With this, thank you very much and good luck.