Answer All the questions on the following page.

1. Two objects collide but do not stick to A) s conserved only if the environment ; B) is conserved only if the colision is efastic. C) Is definitely not conserved. D) is definitely conserved. 2. What is the momentum of a 70 kg object traveling at 20 m/s? A) 300 kg:m/s B) 500 kg-m/s C) 1400 kg'm/s D) 7000 kgm/s 3. A rubber ball and a lump of putty have equal mass and are thrown with equal speed against a wall. The ball bounces back with nearly the same speed with which it hit while the putty sticks to the wall. Which experiences the greater momentum change? A) the ball B) the putty C) Both experience the same momentum change. D) Cannot be determined from the information given. 4. A platform moves at a constant velocity on a horizontal surface. What happens to the velocity of the platform after a sudden rain falls down? A) It increases because the energy is conserved B) It decreases because the energy is conserved C) It remains constant because the momentum is conserved D) It decreases because the momentum is conserved