A ball of mass m falls from a certain height on the pan of mass `M (M gt gt m)` of a spring balance.

A ball of mass m falls from a certain height on the pan of mass `M (M gt gt m)` of a spring balance. The rigidity of the s prin is k. Determine the displacement `Deltax` of the point about which the pointer of the balance will oscillate, assuming that the collisions of the ball with the pan are erfectly elastic.