Grade 8-Quick review

Define force.

Force changes _______ and ________ of an object.

• motion

• shape

The SI unit of force is_________.

Mention the mathematical expression for force_______.

Give one example of contact force.

• kicking a ball

• magnetic force

Define velocity.

Kinetic energy is stored in which form of collision.

• elastic

• inelastic

• completely inelastic

Which law of motion explains why a car at rest stays at rest until another car collides with it?

• Newton’s First Law

• Newton’s Second Law

• Newton’s Third Law

• Law of Gravitation

Pressure is given by the formula:

• P = A ÷ F

• P = F ÷ A

• P = m × a

• P = v ÷ t

In Newton’s 3rd law, action and reaction forces act on the same body.

• True

• False