What is the relative speed of particles?

Answer 1

Well, for atoms to stop moving, the temperature would have to be at 0 K, aka absolute zero. However, that's theoretically impossible. Anyway, solid molecules barely move, "vibrating" against each other in a tightly packed space. For liquid molecules, they can slide past each other and move about, but there's not much space between the particles. As for gas, the particles are much faster than particles of solid or liquid, and the particles move about freely, bumping into each other.

Answer 2

The relative speed of particles refers to the speed at which one particle is moving in comparison to another particle. It is the difference in speed between the two particles, calculated by subtracting one particle's speed from the other's. The relative speed gives insight into how the particles are moving relative to each other.