We wake up in the morning and see all around. If that happened then I would not be able to see anything. Everything would have been dark. If that happened again, the sun suddenly stopped shining. This means that if someone switches off like a light, it will take 6 minutes for the people of the world to understand it. When we turn off the light, it goes off immediately, but when the sun stops shining, why does it take 8 minutes to turn off?
It takes about 8 minutes and 20 seconds for light to reach the earth from the sun. The speed of light is great, but not infinite. How was that speed of light first discovered? Who did?
Einstein’s famous special law of relativity is based on light (especially the speed of light). However, what is light or what is made of it, how it behaves, scientists are still struggling to answer these questions. The behavior of light also seems to be different in different experiments. As a result, different scientists talk differently about light.
Scientist Newton said that light is made up of innumerable small particles and that these particles have no weight. The name of this particle is ‘Photon’. From any source these particles i.E. Photons come out in flocks and scatter around.
Physicist Higgins said that light travels like a wave.
Meanwhile, Max Planck said another thing. According to him, ‘light’ travels in clusters or packets (this is called the quantum theory of light).
We know that light goes straight. That is, it goes straight from the source in the same direction. It does not go in any other direction by bending. However, when passing by a strong magnetic field, the light bends slightly towards that magnetic field.
Light has a specific speed and that is about three hundred thousand kilometers per second in space, that is, it will travel from a source to three hundred thousand kilometers per second.
Light travels fast in space all the time. The denser the medium, the lower the speed of light. For example, the speed at which light travels in space travels through water at three-fourths of its speed. That is, the speed of light in water is 3/4 * 300,000 = 225,000 kilometers per second or two lakh 25 thousand kilometers. And the speed of light in the glass is only two-thirds of the space.
How the speed of light is measured:
In 1675, Wolf Romer, a professor at the University of Copenhagen, was the first to determine the speed of light by observing the eclipse of a satellite of Jupiter while working in Paris. And the same is said, the astronomical method of Romer.
However, the telescope he uses to observe Jupiter’s satellite is Galileo’s invention, and most interestingly, Galileo also discovers the satellite he observes (the satellite’s name is Ayo).
Galileo discovered a telescope on February 7, 1610, and began to look at Jupiter with it. It was during this time that he discovered four satellites of Jupiter. The four satellites are named Ayo, Europa, Ganymede and Callisto and are the largest satellites of Jupiter to date.
Suppose we have a ball on a table far away from us. We see it with a powerful telescope. The ball suddenly fell down from the table. The moment the ball fell, the moment but we do not see the ball fall. Because, the light that will come to us from the ball when the ball falls, it will take time to cross that long distance. That is, when the light of the falling moment crosses that path and reaches our eyes, then we will see the scene of the ball falling.
The work that Roma did this time was to calculate the time of the eclipses that took place between Earth and Jupiter, the smallest and largest of the two, or the distance between them.
And the extra distance that increased during this time, that is, the distance from ‘a’ to ‘b’ was already known (because that is the diameter of the earth). Divide the extra distance by that extra time to find out how far the light is going in a single time i.E. One second. And this is the speed of light.
According to his calculations, the additional distances are: 29,90,00,000 and the additional 1000 seconds, which when divided is 2,99,000 kilometers or 1 lakh 86 thousand miles per second.