5. What force are people using when they put sand or gravel on icy roads in the winter?

6. What type of friction must you overcome when you

ice skate?

7. What force keeps a roller-coaster car on the track?

8. When you wear a seat belt, you are being protected

from possible harm by what force?

9. What has greater inertia, a large car or a small car

moving at the same speed? Why?

10. If someone is playing in a baseball game, what

are three forces or laws of motion that could affect the game?