Newton's 3rd Law of Motion

When a small car pushes a big truck, the truck applies an equal and opposite force on the car.

• False

• True

When a cannon fires a cannonball we observe Newton's third law. Which is the reaction force?

• The cannon moving forward

• The cannon moving backwards

• The cannonball moving backwards

• The cannonball moving forward

Action-reaction pairs can cause a change in motion.

• True

• False

When the person pushes the ground with their foot, the equal and opposite reaction force is

• the ground pushing back on their foot

• when they start to move forward

Force always come in________

• waves

• triplets

• pairs

When a heavy football player and a light one run into each other, who exerts more force

• The light one

• Their force are equal

• The heavy one

The forces in a force pair are in _______ direction

• opposite

• same

A person steps out of the boat and onto the dock.  As the person moves forward onto the dock, the boat moves backward.  Which statement best describes the backward motion of the boat as the person steps forward?

• For every action there is an equal and opposite reaction.
• Every mass exerts a force on every other mass.
• An object at rest tends to stay at rest.
• Friction opposes the motion of an object.

A baseball bat hits a baseball with a force of 100 Newtons. What is the force and its direction exerted by the ball on the bat?

• 100 Newtons, same direction

• 100 Newtons, opposite direction

• 200 Newtons, opposite direction

• 200 Newtons, same direction

The illustration shows the forces in Newtons (N) acting on three different blocks. Which blocks will move under these conditions?

• Blocks 1 and 2

• Blocks 2 and 3

• Blocks 1, 2, and 3

• Blocks 1 and 3