Diathermancy

Diathermancy is like a magical power that some materials have to let heat or light pass through them easily. Think of it like a big gate that some things can easily go through, but others can't.

Imagine you have a very special blanket that you can see through, but it still keeps you warm. That blanket is diathermic, meaning that it lets light pass through easily, but still keeps the warmth in.

Now, imagine you have a piece of metal. Metals are not diathermic. Heat or light can't pass through them easily. It's like they have a small gate that only lets a little bit of warmness or light go through.

This is very important because it helps us understand how different materials react to light and heat. It also helps us understand how some things can be used for certain purposes, like materials that can let light through are great for windows, while metals that don't let heat pass through are great for cooking pans.