A small smooth sphere of mass is moving with velocity when it hits a smooth wall

PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A small smooth sphere of mass

m

is moving with velocity

(2\mathbf{i} - \mathbf{j}) \text{ ms}^{-1}

when it hits a smooth wall. It rebounds from the wall with velocity

(\mathbf{i} + \mathbf{j}) \text{ ms}^{-1}

. Find (1) A unit vector in the direction of the impulse received by the sphere (2) The coefficient of restitution between the sphere and the wall