A car of mass 1ton is moving with a velocity of 25 m/s towards left. A truck of mass 5 ton is moving towards left with a velocity of 3 m/s. If the collision is perfectly elastic, what is the final velocity of the truck in m/s?

Collision is short-duration interaction between two bodies or more than two bodies simultaneously causing change in motion of bodies involved due to internal forces acted between them during this. Collisions involve forces (there is a change in velocity).