Friction and Velocity

1. Which of the following best explains why a ball rolling on a flat surface eventually stops?

• A. Gravity pulls the ball down.

• B. Friction between the ball and the surface slows it down.

• C. The ball's velocity decreases on its own.

• D. Air resistance increases the ball's mass.

2. A 15 kg box is pushed across a floor with a constant velocity. What does this indicate about the forces acting on the box?

• A. The applied force is greater than friction.

• B. The applied force equals the frictional force.

• C. Friction is zero.

• D. Gravity is not acting on the box.

3. Which graph represents an object moving with a constant velocity?

• A. A straight, horizontal line on a velocity-time graph.

• B. A straight, diagonal line on a velocity-time graph.

• C. A curved line on a velocity-time graph.

• D. A straight line on a distance-time graph.

4. A car traveling at 30 m/s comes to a stop in 10 seconds. What is its acceleration?

5. Which situation involves the least amount of friction?

• A. Ice skating on a frozen pond.

• B. Walking on sand.

• C. Dragging a wooden block on concrete.

• D. Pushing a heavy box on carpet.

6. 6. If a car moves at a constant velocity of 20 m/s for 10 seconds, how far does it travel?

7. What happens to the velocity of an object moving on a surface with increasing friction?

• A. Velocity increases.

• B. Velocity decreases.

• C. Velocity remains constant.

• D. Friction does not affect velocity.

8. 8. Identify the force that resists motion between two surfaces in contact.

9. What is the term for the friction that prevents an object from starting to move?

10. 10. Explain how understanding friction and velocity is important in designing safer roads and vehicles.