physics please help
posted by john .
suppose a cart of mass m = 969 g is initial moving at speed v0 = 5.17 m/s. It strikes a spring attached to a fixed wall, comes to a stop, and bounces back at speed vf = 4.48 m/s. Assume the track is frictionless.
a) Find the magnitude of the impulse exerted by the spring on the cart.
b) Find the energy lost in this collision.
c) If the cart was in contact with the spring for 232 ms, find the average force exerted by the spring on the cart.