Question

A student rolled a red basketball across a gym floor toward a blue basketball, which was motionless. When the balls collided, the student observed that the red basketball had stopped moving and concluded that the blue basketball had exerted a force on the red ball. Evaluate the student’s conclusion by answering the following questions.

• What force acted on the red ball during the collision?

• Compare the forces that acted on the two balls during the collision.

• Given that the red basketball stopped moving, predict the motion of the blue basketball after the collision.

• Was the student’s conclusion correct?

Answer 1

1. The blue balls force stopped the red ball, pushing the blue one.
2. The blue ball went from one way and the red ball from the other, causing the two forces to collide and put all force in one.
3. The blue ball will roll some more but stop after some time.
4. Yes.

Answer 2

When the balls collided, the student observed that the red basketball had stopped moving and concluded that the blue basketball had exerted a force on the red ball. Evaluate the student’s conclusion by answering the following questions.