8. A volleyball accelerates due to a constant 11. A parachutist slows down when his parachute force acting on it for 5 seconds, and it reaches opens. Where does the kinetic energy go? a speed of 60 m/s. If the mass of the volleyball A. It is destroyed. is 0.25 kg, what is the constant force? B. It is transformed to heat. A. 3N C. It is transformed to gravitational potential B. 300 N energy- C. 3 m D. It is transformed to elastic potential D. 24 N energy- 9. Synthesize Information Two billiard balls of 12. Identify Snow has been lying on a moun- equal masses moving with equal speeds run tainside. Suddenly, it starts to move down into each other. They hit head on, so their the mountain. Which types of friction are directions are both reversed, What can you say observed in this avalanche? Where does each about their speeds after the collision? type occur? 10. Apply Concepts You have a coin sitting on a card on top of a glass. You want to put the coin into the glass, but you are not allowed 13. Synthesize Information Suppose you are to pick up the card. Think of how you can do on the planet Sloth, where gravity is 1/9 that. Then write a short explanation of why the gravity on Earth. You drop a stone and it works that would make sense to someone measure its speed as it hits the ground. How who doesn't remember Newton's laws of does that speed compare to the speed the motion. same rock would reach falling the same dis- tance on Earth