B. Choose the letter of the correct answer. 1. Which has the greatest friction? a. wet floor c. tiled floor b. sandy floor d. polished floor
2. What force do the brakes on a bicycle produce to stop the bike?
a. pitch c. magnetism b. gravity d. friction
3. What will occur if there is no air resistance?
a. The baseball will land first. b. The baseball will float slowly through the air c. The baseball and the paper will land at the same time d. The paper will float slowly through the air..
4. What makes a rolling ball slow down and stop?
a. air resistance c. brake b. friction d. gravity
5.How is brake useful?
a. It uses friction to make vehicles move faster. b. It uses friction to slow down a moving vehicle. c. It uses friction to move the vehicle to any direction. d. It uses friction to move the vehicle easily.
6. Which shows that friction is undesirable?
a. pushing a furniture b. walking on wet floors c. lighting a matchstick d. using the breaks when approaching a stoplight 7. Which of the following describes the force that holds planets in their orbits?
a. gravity c. rotation b. friction d. revolution
8. What makes a rolling ball slow down and stop? a. brake c. gravity b. friction d. air resistance
9. Why does a car travell faster iin going down than in going up?
a. It is moving against gravity. b. It is being pushed by the wind. c. It is moving towards gravity. d. It is being pulled by the weight of the car
10. What kind of force does the ground exert against your feet? a. gravity c. mass b. friction d. contact​