Consider a steel sphere, of mass, m, colliding elastically head-on at a speed, u, with a stationary identical steel sphere.
a. Use conservation of linear momentum to write a general expression for the total momentum before and after the collision.
b. If the collision is elastic, write a general expression for the total kinetic energy before and after the collision.
c. Show that the initially stationary sphere moves off at speed, u, and the initially moving sphere stops.