Forces and Motion 2021

The upward force exerted on an object falling through air is

• weightless.
• terminal velocity.
• momentum.
• air resistance.

When an object moves in a circular path, it accelerates toward the center of the circle as a result of

• friction.
• terminal velocity.
• momentum. 
• centripetal force.

The statement "to every reaction there is an equal and opposite reaction" is 

• Newton's 1st Law.
• Newton's 2nd Law.
• Newton's 3rd Law.
• Law of conservation of momentum.

The product of mass and velocity gives a quantity known as

• velocity.
• momentum.
• friction.
• inertia.

An object that is in free fall seems to be

• not moving.
• weightless.
• speeded up by air resistance.
• slowed by air resistance.

The relationship among mass, force, and acceleration is explained by

• the conservation of momentum.
• Newton's 1st Law.
• Newton's 2nd Law.
• Newton's 3rd Law.

When two objects collide, their momentum after the collision is explained by 

• the conservation of momentum.
• Newton's 1st Law.
• Newton's 2nd Law.
• Newton's 3rd Law.

A feather will fall through the air more slowly than a brick because of

• momentum.

• gravity.

• air resistance.

• terminal velocity.

The amount of gravitational force between objects depends on their

• masses and the distances between them.
• frictional forces.
• speed and direction.
• inertia.

When a force is exerted on an object, an equal and opposite force is exerted by the object.  These forces are referred to as 

• action-reaction forces.
• centripetal force.
• friction forces.
• gravitational forces.