Sorry if this question has already been considered in this Forum (I'm sure it is but I can't find it now).
A rigid ball slide without friction in an horizontal plane and collide elastically with a wall, the plane of which is perpendicular to the ball's velocity.
During the collision the ball loses its kinetic energy Ek, in the firs part, then re-acquires it in the second part.
How do I write the work-kinetic energy theorem Wext = ΔEk, since the contact point of the ball and wall doesn't move during the process?
A rigid ball slide without friction in an horizontal plane and collide elastically with a wall, the plane of which is perpendicular to the ball's velocity.
During the collision the ball loses its kinetic energy Ek, in the firs part, then re-acquires it in the second part.
How do I write the work-kinetic energy theorem Wext = ΔEk, since the contact point of the ball and wall doesn't move during the process?