Forces and Newton's Laws Test

If net force on an object is 0 Newtons, what does that tell you about the object?

• Its velocity is changing

• It must be standing still

• It could be standing still or it could be moving at a constant velocity

• It is in free fall

Answer explanation

Zero signifies that there is NO acceleration.

The acceleration of an object is directly proportional to

• the position of the object

• the net force on the object

• the velocity of the object

• the object's inertia

Answer explanation

Unbalanced forces are pushes or pulls.

The acceleration of an object is directly proportional to

• the position of the object

• the net force on the object

• the velocity of the object

• the object's inertia

Answer explanation

Unbalanced forces are pushes or pulls.

The net force of kinetic friction on an object sliding on a rough surface is

• perpendicular to the direction of the motion

• directly opposite to the direction of the motion

• in the same direction as the motion of the object

• inversely proportional to the object's mass

Answer explanation

Friction resists the applied force.

According to Newton's First Law, a moving object acted on by a net force of zero

• slows down and stops

• increases its inertia

• decelerates at a constant speed

• moves at a constant rate

Answer explanation

Inertia keeps objects in motion UNLESS an outside force acts upon them.

Newton's Third Law says force pairs are

• equal in magnitude and point in the same direction

• equal in magnitude and point in the opposite directions

• cancel each other out for a net force on each object of zero

• unequal in magnitude because they depend on the masses of the objects

• It is rotating

• It is accelerating

• It is slowing down

• It is moving at a constant speed

Answer explanation

Net force of Zero.

A 42.3 kg rock is at rest on a table. What is the magnitude of the normal force exerted by the table on the rock?

• 42.3 Newtons

• 42.3 kilograms

• 423 Newtons

• 4.23 Newtons

Answer explanation

F = m x a

If you push on a wall with a force of 200 N, what force does the wall push back with?

• -200 N

• 0

• 200 N

• 200 N / 2 = 100 N

A ball has amass of 2 kg. If the acceleration due to gravity is acting on the ball, what is the weight of the ball in Newtons?

• 4.9 N

• .204 N

• 19.6 N

• 11.8 N