Revision game

1

100

• What is the cause of an acceleration?

force

100

• What causes a moving object to change direction?

Force

100

forces arises from direct physical contact between two objects?

contact force

100

• Which of the following is the tendency of an object to maintain its state of motion?

inertia

100

• As an object falls toward Earth,

a.         the object does not exert a force on Earth.         

b.         the object exerts a downward force on Earth.     

c.         Newton’s third law does not apply.       

d.         the upward acceleration of Earth is negligible because of its large mass.

d.         the upward acceleration of Earth is negligible because of its large mass.

2

100

• A newton is equivalent to what quantities?

kg·m/s

100

• A free-body diagram represents all of the following except

a.  the object.   

b.  forces as vectors.     

c.   forces exerted by the object.          

d.  forces exerted on the object.

c.         forces exerted by the object.

100

• A free-body diagram of a ball falling in the presence of air resistance would show

a.         only a downward arrow to represent the force of air resistance.  

b.         only a downward arrow to represent the force due to gravity.     

c.         a downward arrow to represent the force due to gravity and an upward arrow to represent the force of air resistance.       

d.         an upward arrow to represent the force due to gravity and a downward arrow to represent the force of air resistance.

c.         a downward arrow to represent the force due to gravity and an upward arrow to represent the force of air resistance.

100

• A late traveler rushes to catch a plane, pulling a suitcase with a force directed 30.0° above the horizontal. If the horizontal component of the force on the suitcase is 60.6 N, what is the force exerted on the handle?

a.         53.0 N  c.         65.2 N 

b.         70.0 N  d.         95.6 N

b.         70.0 N

100

• If the sign of work is negative,

a.         the force is in the same direction as the displacement.    

b.         the force is perpendicular to the displacement.   

c.         the component of the force that does work is in the direction opposite the displacement.  

d.         the component of the force that does work is perpendicular to the displacement.

c.         the component of the force that does work is in the direction opposite the displacement.

3

100

• A net force of 6.8 N accelerates a 31 kg scooter across a level parking lot. What is the magnitude of the scooter’s acceleration?

   0.22 m/s

100

• Newton’s third law of motion involves the interactions of

two objects and two forces.

100

• A change in the gravitational force acting on an object will affect the object’s

a.         mass.  

b.         coefficient of static friction.     

c.         weight.

d.         inertia.

c.         weight.

100

• There are six books in a stack, and each book weighs 5 N. The coefficient of static friction between the books is 0.2. With what horizontal force must one push to start sliding the top five books off the bottom one?

5 N

100

• Which equation is used to calculate the work done on an object by a force at an angle, , to the displacement?

a.         W = Fd

b.         W = Fdcos    

c.         W = Fdsin     

d.         W = mgsin

b.         W = Fdcos  

4

100

• Assuming no air friction and ay = -g, the horizontal displacement of a projectile depends on the

a.         horizontal component of its initial velocity only.

b.         vertical component of its initial velocity only.   

c.         vertical component of its initial velocity and its time in flight.    

d.         vertical component and the horizontal component of its initial velocity.

d.         vertical component and the horizontal component of its initial velocity.

100

• Which of the following situations describes inertia?

a.         A stationary object tends to resist being moved.

b.         A moving object tends to resist a change in speed.         

c.         A moving object tends to resist a change in direction.    

d.         all of the above

d.         all of the above

100

• A single force acting on an object is represented in a free-body diagram by upward force vector. What is the force vector representing a single force acting on the object that will bring the object into equilibrium?

   

downward arrow

100

• In which situation is the net force acting on a car zero?

a.         The car increases speed and changes direction.  

b.         The car increases speed but does not change direction.   

c.         The car maintains its speed but changes direction.         

d.         The car maintains both its speed and direction.

d.         The car maintains both its speed and direction.

100

• A car traveling at the legal speed limit has velocity +vcar with respect to the road. You are in another car traveling in the opposite direction at the legal speed limit with respect to the road. As the first car approaches you, what is its velocity relative to you?

a.         +vcar    

b.         vcar      

c.         +2vcar  

d.         -2vcar

c.         +2vcar  

5

100

• If a nonzero net force is acting on an object, then the object is definitely

a.         at rest. 

b.         moving with a constant velocity.

c.         being accelerated.        

d.         losing mass.

c.         being accelerated.

100

• The motion of a projectile is characterized by

a.         a_x = a_y = -g.     

b.         a_x = constant and v_y = constant. 

c.         v_x = constant and a_y = -g.          

d.         v_x = constant and v_y = constant.

c.         v_x = constant and a_y = -g.    

100

• A sled is pulled at a constant velocity across a horizontal snow surface.

If a force of 8.0 x 10¹ N is being applied to the sled rope at an angle of 53 to the ground, what is the magnitude of the force of friction of the snow acting on the sled?

48 N

100

• In a free-body diagram of an object, why are forces exerted by the object not included in the diagram?

Forces exerted by the object do not change its motion.

100

• What are the units of the coefficient of friction?

a.         N        

b.         1/N     

c.         N       

d.         The coefficient of friction has no units.

d.         The coefficient of friction has no units.