1. Questions 1-3: A 2000 N crate is being pushed across the level floor at a constant speed of 4.0 m/s by a horizontal force of 600 N. The constant speed of the crate is doubled to 8.0 m/s. Everything else remains as stated in the problem. No justifications are necessary. How is the force of friction affected?

2. How is the coefficient of friction affected?

3. How is the normal force affected?

4. Questions 4-6: This time, the weight of the crate is doubled to 4000 N. Everything else remains as stated in the problem. No justifications are necessary. How is the force of friction affected?

5. How is the coefficient of friction affected?

6. How is the normal force affected?

1. Questions 1-4: A girl stands on a platform scale in an elevator. She weighs 400 N, but the reading on the scale she stands on is 350 N. What is the girl’s weight?

6. Give an example of an object that has acceleration but not speed.