Physics 1 Honors

Homework Packet - Topic 4 - Inertia and Free Particle Motion

• show the work necessary and the answer.

Please, if you are going to write the answers by hand, make it legible, thank you.

1. You kick a soccer ball across a field. It slows down and comes to a stop. You ask your brother to explain what happened to the ball.

He says, "The force of your foot was transferred to the ball, which made it move.When that force ran out, the ball stopped."

Would Newton agree with that explanation? If not, explain how Newton's laws would describe it.

2. Imagine riding a single-speed bicycle. Why do you have to push harder on the pedals to start the bicycle moving than to keep it moving at a constant velocity?

3. What is the net force acting on a 1.0-kg ball moving at a constant velocity?

4. Suppose that the acceleration of an object is zero. Does this mean that there are no forces acting on the object? Give an example using an everyday situation to support your answer.

5. When a basketball player dribbles a ball, it falls to the floor and bounces up. Is a force required to make it bounce? Why? If a force is needed, what is the agent involved?

6. A cart has a net horizontal force acting on it to the right. Jon says that it must be moving to the right. Joanne says no, it could be moving in either direction. Is either of these two correct? If so, explain and describe the velocity and acceleration (if any) of the cart.

7. Before a skydiver opens her parachute, she might be falling at a velocity higher than the terminal velocity that she will have after the parachute deploys.

a.Describe what happens to her velocity as she opens the parachute.

b.Describe the sky diver's velocity from when her parachute has been open for a time until she is about to land.

8. A rock is dropped from a bridge. Earth pulls on the rock and accelerates it downward. According to Newton's third law, the rock also pulls on Earth, but Earth does not seem to accelerate. Explain.

9. Ramon pushes on a bed as shown Draw a free-body diagram for the bed and identify all the forces acting on it. Make a separate list of all the forces that the bed applies to other objects.

\fB C A5.9 kg 0.047 kg T 0.055 m 0.055 m 0.047 kg 5.9 ka