Inverse-square law

The inverse-square law is a rule that says when you move away from something that is giving off light, sound or any kind of energy (like heat), the amount of that energy you receive decreases by a lot.

To understand it better, let's say your friend is holding a flashlight, and they point it towards you from a very close distance. You can see the light very clearly, and it feels bright! But if your friend starts moving away from you while still shining the same flashlight towards you, the amount of light that hits you decreases very quickly.

That's because the light waves spread out as they travel, and the farther they travel, the more they spread out. This means that the same amount of light that was hitting you from a closer distance now has to cover a larger area, so it becomes less concentrated, and it feels less bright.

This rule also applies to things like sound waves and gravitational force. If you're standing close to someone who is speaking, you can hear them clearly, but if they move away, their voice gets softer and harder to hear.

So, the inverse-square law tells us that the farther you are from something that is emitting energy, the weaker that energy will feel. It's like playing a game of catch with a friend. If you stand very close to each other, you can throw the ball really easily, but the farther apart you stand, the more difficult it becomes.