Pyroelectric effect

Alright kiddo, have you ever rubbed a balloon against your hair and then stuck it to the wall? That's called static electricity - when two things rub against each other and create an electric charge. The pyroelectric effect is kind of like that, but with heat instead of rubbing.

So when certain materials get hot or cold, they can actually create an electric charge too. Imagine you have a piece of this material that's shaped like a little pyramid. If you heat it up, the top will become positively charged and the bottom will become negatively charged. Then if you cool it down, it will flip and the top will become negatively charged and the bottom positively charged. This back and forth movement of electric charges is the pyroelectric effect.

Why is this useful? Well, scientists can use materials with this effect to make sensors that can detect changes in temperature. For example, a pyroelectric sensor could tell you when someone walks by because they emit heat and it would trigger the sensor to detect the charge created by the pyroelectric effect. Cool huh?