Light



Light is an important part of our daily lives. Light is something that we humans definitely need. But a lot of us take it for granted, and only remember it in the middle of a science lesson. But what exactly is light? That is what I will explain today. I will explain about what is light, its speed, and some strange facts about light.

First of all, if we want to know about light, we need to know what it actually is. Light is well known as a wave in the electromagnetic spectrum, but some people think that light is a particle. Nobody knows for sure. This causes the wave-particle duality of light. Light behaves as a wave, but in some ways also behaves as a particle. It’s sort of like the Schrodinger’s Box, where there is a cat that is both dead and alive. Does that ring a bell? For now, we’ll save that for another blog.

Next, it’s speed. We all know what the speed of light is: 299,792,458 m/s. But let’s presume that we are in a car moving at 10% the speed of light. What would be the speed of a car moving at the speed of light from your perspective? 90% the speed of light? Nope, it will still appear to be moving at the speed of light. Strange, right?

One last thing: the time when moving at the speed of light. Let’s say you go to outer space at 99% the speed of light and you come back after a year has passed in your time. When you get back, your friend will be 99 years older! If you went at the speed of light, time would nearly stop for you, and an massive amount of years would pass for your friend.

As you should know, light still can be affected by gravity, yet it can always get away. However, there is one exception. Light cannot escape from this object, even with its amazing speed. What is it? Black holes. That’s right, once light goes in a black hole, it can never get out. This is due to the large amount of gravity in a black hole. If you want to know more about this, visit my blog about Black Holes.

That’s it for now, and thanks for reading! Leave a comment if you would like me to do a part 2 or want me to explain more stuff!

~Nat

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