6. A sled travels down a slope and up the side. At which point does it have its greatest kinetic energy?

7. When a car crashes into another, the energy transfer goes into what?

8. The skater has a mass of 50 kg and starts from rest on the first slope from a height of 15 m. The skater rolls down the slope and up the other, up 3.2 m. Predict what would be the minimum kinetic energy, in joules, of the skater.

9. What is gravitational potential energy?