Chapter 2 Review

1

100

A(n) ________ is a push or a pull a. newton c. force b. acceleration d. momentum

c. force

200

A ________ force is the total force felt by an object. a. sum c. strong b. net d. balanced

b. net

300

In order to be ________ forces, their effects must cancel each other out and not cause a change in an object’s motion. a. balanced c. weak b. strong d. normal

a. balanced

400

If the forces acting on an object are unbalanced, then the object will _________. a. stop c. slow down b. speed up d. accelerate

d. accelerate

500

Newton’s first law of motion states that an object at rest or moving at a constant speed will continue to do so until a(n) ______ acts on it. a. inertia c. momentum b. force d. pull

b. force

2

100

_______ is the rubbing force that acts against motion between two touching surfaces. a. Acceleration c. Momentum b. Normal force d. Friction

d. Friction

200

________ allows you to ride a bike without skidding and falling. a. Static Friction c. Rolling Friction b. Sliding Friction d. Gravity

c. Rolling Friction

300

Applying brakes uses _______ to slow a vehicle down. a. static friction c. rolling friction b. sliding friction d. gravity

b. sliding friction

400

The maximum speed an object reaches when the force of gravity is balanced by the force of air resistance is called _______. a. acceleration c. terminal velocity b. balanced velocity d. free fall

c. terminal velocity

500

You hit a wall with a stick. The equal but opposite reaction is ________. a. the wall pushes against you c. you push against the stick b. the stuck pushes against you d. the wall pushes against the stick

d. the wall pushes against the stick

3

100

The gravitation force of any object near Earth’s surface is __________. a. unknown c. Newton’s first law b. friction d. 9.8m/s2

d. 9.8m/s2

200

The force of ___________ exists between any two objects that have mass. a. gravity c. weight b. acceleration d. free fall

a. gravity

300

Newton’s third law explains ______ forces. a. primary and secondary c. kinetic and potential b. action and reaction d. balanced

b. action and reaction

400

You are riding on a bike. In which of the following situations are the forces acting on the bike balanced? a. You pedal to speed up c. You coast to slow down b. You turn at constant speed d. You pedal straight at constant speed

d. You pedal straight at constant speed

500

This is the strongest type of friction that prevents an object from moving when a force is applied is ______________ friction.

Static

4

100

The amount of ________________ in an object is called mass.

matter

200

The point in an object that moves as if all the object’s mass were concentrated at that point is called ________________________________.

center of mass

300

___________________________ occurs when an object changes speed, changes direction, or changes both speed and direction.

acceleration

400

_______________ is the gravitational force on an object’s mass.

weight

500

A ___________ is the the SI unit of force.

newton

5

100

Why does friction never speed up an object?

Friction will never speed up an object because it always opposes motion.

200

A marble is lying in the middle of the floor. Define Newton’s first law of motion and use it to describe what will happen to the marble.

Newton’s first law states that “an object at rest will remain at rest until a net force acts on it”; therefore, the marble will remain in the middle of the floor until a net force is applied to it.

300

A broom strikes the marble while you are sweeping. Define Newton’s second law of motion and use it to describe what happens to the marble.

Newton’s second law of motion states “an object acted upon by a force will accelerate in teh direction of the force”. The marble will accelerate in the direction of the force that the broom applied to it.

400

Define Newton’s third law of motion and use it to describe what interaction there is between the marble and the broom.

Newton’s third law of motion states that “for every action there is an equal (size) but opposite (direction) reaction. When the broom pushes the marble, the marble pushes the broom with the same amount of force but in the opposite direction.

500

If action and reaction force pairs are equal and opposite, how can anything move? Give an example of equal and opposite force pairs.

Action and reaction force pairs do not cancel because they do not act on the same object, instead, they act on each other. An example of an equal and opposite force pair is jumping off the ground. When you jump, you exert a force downward on the ground, and the groud exerts an equal force but in the opposite direction (upward).