When they made the first clock, how did they know what time it was? How did they set it?
When the first clock was invented, How did they know what time it was?
Who invented the clock? Who invented clocks? Who invented the time machine? What is clock? What's the origin of the word o'clock? What is the origin of the word o'clock? When did humans first start counting the years? When did the modern era begin? Why was time created? How did time begin to exist? Was time created first or universe? Is there an official clock in the world? When did we start measuring time? How is the time on a Speaking Clock recorded? Where did time come from? Did time machine exist? What are the exact times in which hands of a clock divide it to three equal segments? Why was Daylight Saving Time invented? When did we start measuring time in seconds? Who decided what duration will be one second? Why did we divide an hour in 60 minutes and a minute in 60 seconds? Why not 100 minutes or 100 seconds? How did this system come to exist? What is the measure of the angle formed by the minute and hour hands of a clock at 1:50? Why time machine is not yet invented? Is it possible to invent it? What is the first thing that humans invented? Who invented the light year? What is clock in communication? From which century did modern era start? Who invented the modern periodic table? What is the earliest recorded date, i.e. we could calculate that it was May 23rd year XXXX BCE and it was a Tuesday (for example)? What is it that makes a second a second in clocks (analog/digital)? What defines time in clocks? Special Relativity: Whose clock shows more time elapsed? Why clock is used in digital circuits?