Group velocity

Group velocity is like telling your friends to move together in a race.

Imagine you and your friends are in a race together. You all start at the same time and run at the same speed. But then, one of your friends slows down a bit. Since you are all in a group, you slow down too to stay together. This is called the group velocity.

In science, this happens with waves. Waves can travel in a group, like a bunch of friends running in a race. But just like how one friend slowing down affects the group velocity, different parts of the wave moving at different speeds affects the group velocity.

For example, sound waves travel as a group of vibrations in the air. If some parts of the wave travel faster than others, this affects the group velocity of the sound wave. Scientists use group velocity to understand how waves move together in groups.