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Name: ________________________ Class: ___________________ Date: __________
ID: C
Chapter12. Forces
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. A force is continuously applied to an object, causing it to accelerate. After a period of time, however, the
object stops accelerating. What conclusions can be drawn?
a. The mass of the object has increased.
b. Gravity on the object has increased.
c. The object is experiencing some kind of friction.
d. The momentum of the object has reached a maximum.
____
2.
Each figure below shows a force measured in newtons pushing
on a block. If there are no other forces pushing on the block, in which case is the acceleration of the block
greatest?
a.
b.
A
B
c.
d.
C
D
____
3. If an equal force is applied to two cars of equal mass, Car A and Car B, Car A will have _____ acceleration as
(than) Car B.
a. the same
c. less
b. greater
d. the opposite
____
4. Weight is best described as
a. an object’s resistance to acceleration.
b. what causes an object to fall.
c. the downward force exerted on an object due to gravity.
d. a force solely dependent on an object’s mass.
____
5. What unbalanced force is needed to give a 976 kg vehicle an acceleration of 2.50 m/s 2?
a. 3.90  102 N
c. 2.44  103 N
2
b. 3.90  10 lb
d. 2.44  103 lb
____
6. How much does a 59.0 kg woman weigh on Earth?
a. 6.02 N
c. 145 lb
b. 59.0 lb
d. 578 N
1
Name: ________________________
ID: C
____
7. Which of the following is true?
a. Weight and mass are proportional but not equal.
b. Weight is gravitational force an object experiences due to its mass.
c. The weight of an object on Earth is greater than the weight of the same object on the
moon, but the object’s mass stays the same.
d. All of the above
____
8. Which object has the greatest inertia?
a. a tennis ball
b. a bowling ball
____
c.
d.
a beach ball
a volleyball
9. Which of the following objects exerts a gravitational force?
a. a bowling ball
c. a feather
b. a book
d. All of the above
____ 10. Of the following, the greatest gravitational force would occur between
a. a marble and a baseball 5 meters apart.
b. a loaded freighter on the high seas and Earth.
c. the moon and an astronaut standing on the moon.
d. the moon and Earth.
____ 11. A tug-of-war that results in one team pulling the other across the line is an example of
a. action forces.
c. balanced forces.
b. reaction forces.
d. unbalanced forces.
____ 12. How does the total momentum of two objects before a collision compare with the total momentum after the
collision?
a. It is the same.
c. It is equal to zero
b. It is less.
d. It is greater.
____ 13. The SI unit of force, named after the scientist who described the relationship between motion and force, is
called the
a. newton.
c. curie.
b. einstein.
d. pasteur
____ 14. The force exerted on the racket by a hit tennis ball is the
a. gravitational force.
c. acceleration.
b. reaction force.
d. action force.
____ 15. A force of 240.0 N causes an object to accelerate at 3.2 m/s2. What is the mass of the object?
a. 0.013 kg
c. 240 kg
b. 75 kg
d. 768 kg
____ 16. What is the reaction force when you place a cup on a table?
a. the force of the cup on the table
c. the force of gravity on the table
b. the force of the table on the cup
d. the force of gravity on the cup
____ 17. Which of the following will result in the greatest acceleration?
a. 56 N acting on a 1-kg box
c. 23 N acting on a 2-kg box
b. 56 N acting on a 2-kg box
d. 23 N acting on a 5-kg box
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Name: ________________________
____ 18.
ID: C
A driver is headed north at 50 km/hr. A box is sitting on the seat next
to him. What action by the driver would most likely cause him to observe the box appear to slide
toward the driver?
a. applying the brakes
c. making a turn to the east
b. speeding up to 60 km/hr
d. making a turn to the west
____ 19. In the absence of air resistance, how would the acceleration of a 1.5 kg book and the acceleration of a 15 kg
rock differ if the objects were dropped from the same height?
a. The book would accelerate twice as fast as the rock.
b. The rock would accelerate twice as fast as the book.
c. The book would accelerate ten times as fast as the rock.
d. They would not differ; they would be the same.
____ 20. Orbital motion is a combination of
a. mass and friction.
b. forward motion and free fall.
c.
d.
acceleration and gravity.
weight and vertical velocity.
____ 21. The tendency of an object at rest to remain at rest is
a. inertia.
c. free fall.
b. momentum.
d. acceleration.
____ 22. The law that states that every object maintains constant velocity unless acted on by an unbalanced force is
a. Newton’s first law of motion.
b. Newton’s second law of motion.
c. Newton’s third law of motion.
d. the law of conservation of momentum.
____ 23. Whenever a force is exerted, another force occurs that is _____ in size, and _____ in direction.
a. equal, same
c. equal, opposite
b. smaller, same
d. smaller, opposite
____ 24. When a moving bowling ball hits a pin, some of the ball’s momentum
a. doubles in force.
c. is transferred to the pin.
b. increases the pin’s mass.
d. is lost.
____ 25. A 0.25 kg steel ball experiences a net force of 1.15 N as it rolls down a ramp. What is the acceleration of the
ball?
c. 1.4 m/s2
a. 0.29 m/s2
2
b. 0.90 m/s
d. 4.6 m/s2
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Name: ________________________
ID: C
____ 26. When the velocity of an object changes, it is acted upon by a(n)
a. force.
c. momentum.
b. inertia.
d. deceleration.
____ 27. What is the unbalanced force that slows down a ball rolling across the floor?
a. the force of friction
c. the force of inertia
b. the force of gravity
d. the force of momentum
____ 28. The following graph charts the speeds of three objects in motion.
At the 1s mark, which objects have equal momentum?
a.
b.
the bicycle and the rock
the rock and the bowling ball
c.
d.
the bowling ball and the bicycle
all three objects have the same
momentum.
____ 29. Earth pulls on the moon and holds the moon in its orbit. The moon pulls on Earth with an equal and opposite
force. This is an example of
a. Newton’s first law.- Inertia
c. Newton’s third law. - Action/Reaction
b. Newton’s second law. - F=ma
d. None of the above
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Name: ________________________
ID: C
____ 30. Read the passage below. Then, answer the questions that follow.
A REGULAR VISITOR
A microgravity environment is one in which the apparent weight of an object is much less
than its weight on Earth. The term microgravity is used instead of weightlessness because every
object has some weight, though that weight may be so minuscule as to be undetectable. Because
every object in the universe exerts a gravitational pull on every other object, every object possesses
weight.
Microgravity occurs whenever an object is in free fall. Scientists achieve micro gravity
environments in a number of ways. Drop towers and research aircraft provide it for up to 20s. The
Shuttle and the International Space Station can provide it for months.
A rocket ship that is accelerating by firing its rockets cannot provide microgravity. Even if
the rocket is accelerating uniformly, force is applied to the rocket by the gases escaping out the back.
This force must be transferred to each part of the ship through either pressure or tension, and thus
weightlessness is not experienced.
When the Shuttle is orbiting, it is in constant motion around the Earth. Why isn't this motion
experienced as weight?
a.
b.
There is no net force acting on the
c.
Shuttle.
The Shuttle's mass is not large enough d.
to exert a measurable gravitational
pull.
The Earth is exerting the same pull on
both the Shuttle and its passengers.
The Earth is too far away to have a
measurable gravitational effect.
____ 31. Near Earth’s surface, the strongest gravitational force would occur between an elephant and
a. the sun.
c. a cat.
b. the moon.
d. Earth.
____ 32. The gravitational force between two objects depends on masses of objects and
a. accelerations of objects.
c. speeds of objects.
b. distance between objects.
d. sizes of objects.
____ 33.
Two identical cars travel at 45 miles per hour toward the center of the
intersection (point A, as shown above) with equal force. The cars collide at the intersection. If after they
collide the cars stick to each other and move together, they will come to rest closest to
a.
b.
Location A
Location B
c.
d.
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Location C
Location D
Name: ________________________
ID: C
____ 34. Which statement about weight is incorrect?
a. An object weighs more on the moon than it weighs on Earth.
b. A change in an object’s location can change the object’s weight.
c. An object’s weight is directly proportional to its mass.
d. The weight of an object depends on gravity.
____ 35. If the net force on an object is zero, then the object has
a. reaction forces.
c. balanced forces.
b. action forces.
d. unbalanced forces.
Short Answer
36.
A snowboarder begins his run from rest (point 1) on top of a hill. He moves straight down the slope until
he reaches the bottom of the hill (point 4) and the ground levels off. The snowboarder continues to move
horizontally across the level ground and eventually comes to a stop (point 5).
Using the same board, the snowboarder decides to make another run down the hill to see if he can
increase his speed. Describe one thing the snowboarder could do to increase his speed on the slope.
Explain why this would cause his speed to increase. (2 points)
37. Why can the shuttle (in question 30) provide microgravity only after it achieves orbit?
(2 pts)
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Name: ________________________
ID: C
38. A scientist performs the following experiment in a low friction environment.
Assume that the experiment will be repeated in less “ideal” conditions
where the effects of friction on the motion of the box cannot be ignored. Predict the effect that significant
friction would have on the acceleration of the box as it slides down the incline. Explain the cause of the
predicted effect. (2 points)
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ID: C
Chapter12. Forces
Answer Section
MULTIPLE CHOICE
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SHORT ANSWER
36. ANS:
Answers will vary. Friction can be reduced. Momentum increased.
PTS: 2
37. ANS:
Prior to achieving orbit the shuttle is accelerating. Acceleration is causing a net force. Net force is
transferred through the shuttle to the objects within it.
PTS: 3
38. ANS:
acceleration will be less because friction will slow the box down.
PTS: 2
2