Lambert's cosine law

Lambert's cosine law is a rule that helps us understand how much light is shining on a surface.

Imagine you are playing in a park on a sunny day. The sun is shining brightly and the light is hitting everything around you. Lambert's cosine law tells us that how much light is shining on an object depends on the angle at which the light hits it.

Let's take a balloon as an example. When the sun is directly overhead, the top of the balloon gets the full amount of light. But if the sun starts to go down, the light hits the balloon at an angle, and the amount of light that hits the top decreases.

Lambert's cosine law tells us that the amount of light that hits the balloon is proportional to the cosine of the angle at which the light hits it. So, if the angle is 45 degrees, the amount of light that hits the balloon is less than if the angle was 0 degrees (directly overhead).

In simpler terms, Lambert's cosine law says that the amount of light that hits a surface depends on the angle at which it hits the surface. The closer the angle is to 0 degrees, the more light it will get. But as the angle gets bigger (approaching 90 degrees), the amount of light that hits the surface decreases.