How can you block all light completely?

You can block all light completely by making something so thick and dark that not even a single ray can pass through.

Imagine you're in a room with a bright lamp on. Now, picture yourself covering the lamp with a big, thick blanket, the kind you use to stay warm at night. The more layers of the blanket, the darker and cozier it gets. If you pile up many blankets one after another, eventually there's no light left, it’s like nighttime!

Think about going into a deep cave. At first, you might see some light from the entrance, but as you go deeper and deeper, the cave gets darker and darker until it's completely black. That’s because the rock walls are blocking all the light, just like your pile of blankets!

So whether it’s blankets or caves, if something is really thick and dark, it can block all the light, just like a super strong curtain for sunlight!