A ball strickes a horizontal floor at `45^(@). 25%` of its kinetic energy is lost in collision. Find the coefficient of restitution.

A ball strikes a horizontal floor at 45^(@) . 25% of its kinetic energy is lost in collision. Find the cofficient of resultation

A ball strickes a horizontal floor at an angle theta = 45^@ with the normal to floor. The coefficient of restitution between the ball and the floor is e = 1//2 . The fraction of its kinetic energy lost in the collision is.