Science G8_Unit Test 2

Gravitational potential energy is influenced by

• Mass and height above ground

• Weight and height above ground

• Weight and speed

• Mass and speed

What is gravity?

• A force that pulls objects towards each other as a result of their masses.

• A force that pushes or pulls an object as a result of its velocity.

• A force that pushes or pulls objects towards each other as a result of their charges.

• A force that resists a change in motion as a result of its mass.

Acceleration includes: (Circle all that apply)

• objects speeding up.

• objects slowing down.

• objects changing direction.

• none of the above.

When brakes are applied to a moving car, the car decelerates but you do not. What causes your body to continue moving?

• Friction

• Inertia

• Velocity

• Net force

Which is not an example of a noncontact force?

• Friction

• Magnetic force

• Electric force

• Gravity

Newton's first law of motion states that:

• an object at rest will remain at rest unless acted upon by a nonzero net force.

• if one object exerts a force on another object, then the second object exerts a force of equal strength in the opposite direction on the first object.

• the rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of the force.

• the rate at which velocity changes is influenced by speed and direction.

When is there static friction between your desk and the floor?

• When the chair stands still.

• When the chair falls to the floor.

• When you lift the chair.

• When you slide your chair under your desk.

Bella puts an iron block in a bucket of water. The block sinks. Which of the following forces is acting on the block?

• The force of the liquid pushing up on the block.

• The force of gravity pulling down on the block.

• The force of the liquid pulling down on the block

If two forces have the same direction you must ______ to find the net force.

• subtract

• add

• divide

• multiply

What happens to the gravitational force between two objects as the bodies become farther apart from each other?

• The gravitational force stays the same.

• The gravitational force begins to repel the objects.

• The gravitational force decreases.

• The gravitational force increases.