Balance and Unbalance Forces 7

What happens when balanced forces act on an object?

• The object speeds up

• The object remains at rest or moves at a constant speed

• The object changes direction

• The object accelerates

What is Newton's First Law also called?

• Law of Acceleration

• Law of Universal Gravitation

• Law of Inertia

• Law of Action and Reaction

Newton's First Law states that an object in motion will stay in motion unless acted upon by an (a)   force.

The acceleration of an object is directly proportional to the applied force and inversely proportional to its (a)   .

When a car suddenly stops, passengers move forward because of (a)   .

The image shows a person pushing a box. If the force applied is greater than the friction, what will happen?

• The box will remain still

• The box will move in the direction of the push

• The box will rise into the air

• The box will disappear

The force keeping the roller coaster moving in a circular path is called:

• Gravitational force

• Friction

• Centripetal force

• Unbalanced force

What force is opposing the motion of the box in the image?

(a)  

According to Newton's Second Law, force is calculated using the formula F = ____ x ____.

• velocity x time
• energy x mass
• mass x acceleration
• force x distance

Which of the following is an example of unbalanced forces?

• A car traveling at a constant speed on a straight road

• A person sitting on a chair

• A soccer ball being kicked

• A book resting on a table