Group velocity

Group velocity is the speed at which a group of waves or a wave packet travels through a medium. It represents how quickly the overall shape or information carried by the waves moves forward. Think of it like a convoy of cars: the group velocity is how fast the entire convoy moves, not just individual cars. In physics, this concept helps describe how signals or energy propagate, especially in contexts like light and sound waves, and can differ from the speed of individual wave parts depending on the medium's properties.