Question

A bullet of mass 20 g, travelling at a speed of 350 m/s, strikes a steel plate at an angle of 30 degree with the plane of plate. it ricochets off at the same angle, at a speed of 320 m/s. What is the magnitude of the impulse that the steel plate gives to the projectile ?If the collision with the plate takes place over a time delta t=10^3 s, what is the average force exerted by the plate on the bullet?