Force and Motion REVIEW

Two girls are pulling on opposite ends of a thick rope. Both girls pull on the rope with the same force but in opposite directions. If both girls continue to pull with the same force, what will most likely happen? 

• One girl will pull the other toward her.
• Both girls will stay in the same place. 
• Gravity will cause the rope to sag. 
• The rope will break.

When a bird flies, its wings push air downward. As a result the air pushes back upward on the bird. Which law of motion most applies to the way the wings of a bird beat? 

• Every action has an equal and opposite reaction
• The rate of acceleration of an object depends on the amount of force applied.
• Objects in motion tend to remain in motion until acted upon by an another force. 
• Force is defined by mass times acceleration

A student walking quickly while carrying an orange on his lunch tray stops suddenly. The orange will most likely roll off the tray due to

• inertia of the orange. 
• centripetal force of the orange
• the friction acting on the orange.
• the balanced forces acting on the orange.

 Alesia is taking an all­ day ride on her bicycle. The graph shows how far she is from home at different times during her ride.  During which time period is Alesia moving fastest?

• 0–1 hours 
• 3–4 hours 
• 4–5 hours
• 6–7 hours 

Angela blows air into a balloon and holds the end of it closed with her fingers. When she lets go of the end of the balloon, Angela observes that the release of the air propels the balloon.  The propelling of the balloon from the release of the air is an example of which of Newton’s laws? 

• The force of an object is the product of its mass multiplied by its acceleration. 
•  A force of attraction exists between any two objects with mass. 
•  For every action, there is an equal and opposite reaction.
• An object in motion tends to stay in motion unless an unbalanced force acts upon it. 

The graph shows the motion of four cars. All four cars are moving east.   
Which car has a constant velocity? 

• 1
• 2
• 3
• 4

A student reads his paper on friction to the class. Which statement should he include in his paper if he wants to present accurate information? 

• Friction increases mechanical advantage
• Friction opposes the direction of movement. 
• Friction makes movement of an object easier.
• Friction reduces the amount of work used to move an object. 

Kilometers per hour (kph) is a unit that describes which of the following?

• velocity
• direction
• position
• speed

What is speed?

• Speed is how far something travels in one hour.
• Speed is how fast it takes something to travel a set distance
• Speed is the distance something travels in a set amount of time.
• Speed is the change in velocity of something.

When an object's distance from another object is changing, the object is .... 

• under pressure.
•  in motion
• not moving.
• changing reference point.