What is Speed of light in a vacuum?

The speed of light in a vacuum is how fast light travels when it’s not blocked or slowed down by anything else.

Imagine you’re on a really fast scooter, like the fastest one you’ve ever seen. That's kind of what light does when it's zooming through empty space, like the sky above us. It doesn’t have to stop for traffic lights or people walking in front of it. It just goes zoom all the way!

A vacuum means there’s nothing around, no air, no water, no clouds, just empty space. Think about blowing up a balloon and then popping it, that's kind of like a vacuum in a small part of your room.

In a vacuum, light can go as fast as it possibly can. It travels at about 299,792 kilometers per second, which is really, really fast! That means if you were riding on a beam of light, you'd go from one end of the Earth to the other in less than a second!

So next time you see sunlight streaming through a window, remember, that light was traveling through space like it had nowhere else to be!