2. An empty (assume massless) crate is on top of a stiff spring when a 5 kg bowling ball is placed slowly into the crate. The spring compresses 10 cm and the ball is at rest. a. What is the spring's spring constant? b. Another bowling ball (m₂-10 kg) is slowly added to the crate. How much further does the crate drop? c. At this point (with two bowling balls in the crate), the crate is 1 meter above the ground. What is the entire potential energy of the two bowling balls? Include both elastic and gravitational potential energy. d. One of the bowling balls just barely rolls out of the crate. What happens to the remaining bowling ball in the crate? e. At what velocity does the ball which fell out of the crate hit the ground? f. How high above the ground will the second bowling ball (the one that stayed in the crate) go?

Problem 4: Speed deamplifier. In the figure above on the right, block 1 of mass m1 slides along an x-axis on a frictionless floor at speed 4 m/sec.Then it undergoes a one-dimensional elastic collision with stationary block 2 of mass m2 = 2m1. Next, block 2 undergoes a one-dimensional elastic collision with stationary block 3 of mass mz = 4m1. What then is the speed of block 3? Answer: 16 m/sec or 1.78 m/sec.