Retest 6.7A-C

The photo shows evidence of meteorites colliding with the moon. According to Newton’s third law, which statement accurately describes these collisions?

• During each collision, the moon exerted a greater force on each meteorite than each meteorite exerted on the moon.

• The moon and meteorites exerted equal but opposite forces on each other.

• The collisions were so small that no forces acted on either the moon or the meteorites during the collisions.

• Because the moon has no atmosphere, Newton’s third law cannot be applied to the collisions between the moon and meteorites.

How could you increase the gravity between two objects?

CHOOSE TWO

• Increase the mass of one or both of the objects.

• Decrease the mass of one or both of the objects.

• Increase the distance between the objects.

• Decrease the distance between the objects.

A boy pushes against the trunk of a tree with his hands. Choose the TWO statements about the acting forces that are correct

• The tree does not exert any force on the boy.

• The ground exerts an upward force against the tree.

• The boy exerts more force on the tree than the tree exerts on the boy.

• The forces exerted by the boy and the tree are exerted in the same direction.

• Any object that touches the tree in the same way as the boy’s hands will exert force on the tree.

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

• The cannon moving forward

• The cannon moving backward

• The cannonball moving forward

• The cannonball moving backward

When does an object have no kinetic energy?

• When it is at rest

• When it is moving very slowly

• When the only force acting on it is gravity

• When it has no electrical charge