Force and motion

The diagram below show the forces acting on a soccer ball. In which of the diagrams will the ball remain motionless? (W, X, Y, or Z?

Jupiter has about 317 times more mass than Earth. What can you conclude about their gravity from this fact?

______ is a contact force that is applied to an object by a person or another object.

Four toy cars were pushed on a surface with the same force. They traveled a distance before coming to a stop. The graph shows the distance and time plotted for the motion of the four toy cars. Which car is the fastest car?

In the diagram below, a girl sits on a sled and slides down a hill of snow. Which arrow represents the force of friction opposing the motion of the sled down the hill?

demonstrate the example of a spring force.

Two boys are pulling the rope with the same amount of force. What will happen?

A child is riding her bike on a straight path. A friend applies a force on the bike from her back. How will the motion of the bike change?

Which boy will be able to go furthest? Why?

______ is a contact force that resists the sliding motion of two surfaces that are touching.

______ is a noncontact force. It is an attractive force that exists between all objects that have mass.