A demolition derby is a car-crashing contest. Suppose an 800-kg car moving at 20 m/sec crashes into the back of and sticks to a 1200-kg car moving at 10 m/sec in the same direction.

A demolition derby is a car-crashing contest. Suppose an 800-kg car moving at 20 m/sec crashes into the back of and sticks to a 1200-kg car moving at 10 m/sec in the same direction.

a. Is this collision elastic or inelastic? Why?

b. Calculate the momentum of each car before the collision.

c. What is the total momentum of the stuck together cars after the collision? Why?

d. What is the speed of the stuck together cars after the collision?