Download ExamView - Newton`s Laws Review.tst

Name: ________________________ Class: ___________________ Date: __________
ID: A
Newton's Laws Review
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. Instantaneous speed is measured
a. at the starting point.
b. when the object reaches its destination.
c. at a particular instant.
d. over the duration of the trip.
____
2. A car traveled 60 km in 2 hours, 84 km in the next 1 hour, and then 68 km in 2 hours before reaching its
destination. What was the car’s average speed?
a. 212 km/h
c. 148 km/h
b. 42 km/h
d. 1060 km/h
____
3. The slope of a line on a distance-time graph is
a. distance.
c.
b. time.
d.
speed.
displacement.
____
4. A horizontal line on a distance-time graph means the object is
a. moving at a constant speed.
c. slowing down.
b. moving faster.
d. at rest.
____
5. What is the speed of a bobsled whose distance-time graph indicates that it traveled 100 m in 25 s?
a. 4 m/s
c. 0.25 mph
b. 2500 m/s
d. 100 m/s
____
6. A distance-time graph indicates that an object moves 100 m in 4 s and then remains at rest for 6 s. What is the
average speed of the object?
a. 50 m/s
c. 10 m/s
b. 25 m/s
d. 100 m/s
____
7. A river current has a velocity of 5 km/h relative to the shore, and a boat moves in the same direction as the
current at 5 km/h relative to the river. How can the velocity of the boat relative to the shore be calculated?
a. by subtracting the river current vector from the boat’s velocity vector
b. by dividing the river current vector by the boat’s velocity vector
c. by multiplying the vectors
d. by adding the vectors
____
8. The rate at which velocity changes is called
a. speed.
b. vectors.
____
c.
d.
acceleration.
motion.
9. Which example identifies a change in motion that produces acceleration?
a. a speed skater moving at a constant speed on a straight track
b. a ball moving at a constant speed around a circular track
c. a particle moving in a vacuum at constant velocity
d. a vehicle moving down the street at a steady speed
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Name: ________________________
ID: A
____ 10. Objects in free fall near the surface of the Earth experience
a. constant speed.
c. constant acceleration.
b. constant velocity.
d. constant distance.
____ 11. Which example describes constant acceleration due ONLY to a change in direction?
a. increasing speed while traveling around a curve
b. an object at rest
c. traveling around a circular track
d. an object in free fall
____ 12. Suppose you increase your walking speed from 1 m/s to 3 m/s in a period of 1 s. What is your acceleration?
c. 4 m/s2
a. 2 m/s2
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b. 5 m/s
d. 3 m/s2
____ 13. An object moving at 30 m/s takes 5 s to come to a stop. What is the object’s acceleration?
a. 30 m/s2
c. –6 m/s2
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b. –30 m/s
d. 6 m/s2
____ 14. The slope of a speed-time graph indicates
a. direction.
b. acceleration.
c.
d.
velocity.
speed.
____ 15. A speed-time graph shows that a car moves at 10 m/s for 10 s. The car’s speed then steadily decreases until it
comes to a stop at 30 s. Which of the following describes the slope of the speed-time graph from 10 s to 30 s?
a. linear, horizontal
c. linear, sloping downward
b. curved, upward
d. linear, sloping upward
____ 16. An object that is accelerating may be
a. slowing down.
b. gaining speed.
c.
d.
changing direction.
all of the above
____ 17. A train approaching a crossing changes speed from 25 m/s to 10 m/s in 240 s. How can the train’s
acceleration be described?
a. The train’s acceleration is positive.
b. The train is not accelerating.
c. The train will come to rest in 6 minutes.
d. The train’s acceleration is negative.
____ 18. What is instantaneous acceleration?
a. how fast a speed is changing at a specific instant
b. how fast a velocity is changing at a specific instant
c. how fast a direction is changing at a specific instant
d. all of the above
____ 19. Which of the following statements is true?
a. An object that is accelerating is always changing direction.
b. An object has an instantaneous acceleration, even if the acceleration vector is zero.
c. An object at rest has an instantaneous acceleration of zero.
d. Instantaneous acceleration is always changing.
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Name: ________________________
____ 20. The SI unit of force is the
a. joule.
b. kilogram.
ID: A
c.
d.
meter.
newton.
____ 21. Which of the following relationships is correct?
a. 1 N = 1 kg
c.
b. 1 N = 1 kg·m
d.
1 N = 1 kg·m/s
1 N = 1 kg·m/s2
____ 22. When an unbalanced force acts on an object,
a. the object’s motion does not change.
b. the object accelerates.
the weight of the object decreases.
the inertia of the object increases.
c.
d.
____ 23. What kind of friction occurs as a fish swims through water?
a. fluid
c. sliding
b. rolling
d. static
____ 24. As you push a cereal box across a tabletop, the sliding friction acting on the cereal box
a. acts in the direction of motion.
b. equals the weight of the box.
c. is usually greater than static friction.
d. acts in the direction opposite of motion.
____ 25. The forces acting on a falling leaf are
a. air resistance and fluid friction.
b. gravity and air resistance.
c.
d.
gravity and static friction.
weight and rolling friction.
____ 26. The property of matter that resists changes in motion is called
a. friction.
c. inertia.
b. gravity.
d. weight.
____ 27. An orange might roll off your cafeteria tray when you stop suddenly because of
a. the balanced forces acting on the orange.
b. the centripetal force acting on the orange.
c. the friction forces acting on the orange.
d. the orange’s inertia.
____ 28. According to Newton’s second law of motion, the acceleration of an object equals the net force acting on the
object divided by the object’s
a. mass.
c. velocity.
b. momentum.
d. weight.
____ 29. If a force of 12 N is applied to an object with a mass of 2 kg, the object will accelerate at
c. 6 m/s2.
a. 0.17 m/s2.
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d. 12 m/s2.
b. 24 m/s .
____ 30. Your weight equals your
a. mass.
b. mass divided by the net force acting on you.
c. mass times the acceleration due to gravity.
d. mass times your speed.
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Name: ________________________
ID: A
____ 31. The acceleration due to gravity on the surface of Mars is about one third the acceleration due to gravity on
Earth’s surface. The weight of a space probe on the surface of Mars is about
a. nine times greater than its weight on Earth’s surface.
b. three times greater than its weight on Earth’s surface.
c. one third its weight on Earth’s surface.
d. the same as its weight on Earth’s surface.
____ 32. Newton’s third law of motion describes
a. action and reaction forces.
b. balanced forces.
c.
d.
centripetal forces.
net force.
____ 33. In which of the following are action and reaction forces involved?
a. when a tennis racket strikes a tennis ball
b. when stepping from a curb
c. when rowing a boat
d. all of the above
Completion
Complete each statement.
34. The SI unit for measuring ____________________ is the meter.
35. Displacement and velocity are examples of ____________________ because they have both magnitude and
direction.
36. v 
d
is the equation that defines _________________________.
t
37. A constant slope on a distance-time graph indicates ____________________ speed.
38. The difference between speed and velocity is that velocity indicates the ____________________ of motion
and speed does not.
39. A distance-time graph indicates an object moves 20 km in 4 h. The average speed of the object is
____________________ km/h.
40. Because its ____________________ is always changing, an object moving in a circular path experiences a
continuous change in velocity.
41. A moving object does not ____________________ if its velocity remains constant.
42. Freely falling objects accelerate at 9.8 m/s2 because the force of ____________________ acts on them.
43. The velocity of an object moving in a straight line changes at a constant rate when the object is experiencing
constant ____________________.
44. The acceleration of a moving object is calculated by dividing the change in ____________________ by the
time over which the change occurs.
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Name: ________________________
ID: A
45. A car that increases its speed from 20 km/h to 100 km/h undergoes ____________________ acceleration.
46. ______________________________ is how fast a velocity is changing at a specific instant.
47. A push or pull is an example of a(an) ____________________.
48. The force that opposes the motion of objects that touch as they move past each other is called
____________________.
49. The tendency of an object to resist any change in its motion is called ____________________.
50. During a head-on auto collision, ____________________ causes a passenger in the front seat to continue
moving ____________________.
51. When you push on a wall, the ____________________ pushes back on you.
Short Answer
52. Bus A travels 275 m in 13 s. Bus B travels 290 m in 13 s. Both vehicles travel at constant speed. How do the
distance-time graphs for these two speeds differ?
53. What is the significance of the slope in a distance-time graph?
54. What types of changes in motion cause acceleration?
vf  vi
is the equation for calculating the acceleration of an object. Write out the relationship shown in the
t
equation, using words.
55. a 
56. In the equation for acceleration, a 
vf  vi
, how can you describe acceleration if the numerator is negative?
t
57. What information does the slope of a speed-time graph provide?
58. The slope of the curve at a single point on a distance-time graph of accelerated motion gives what
information?
59. How can you double the acceleration of an object if you cannot alter the object’s mass?
60. How are the size and direction of action-reaction forces are related?
Problem
61. During a race, a runner runs at a speed of 6 m/s. 2 seconds later, she is running at a speed of 10 m/s. What is
the runner’s acceleration? Show your work.
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Name: ________________________
ID: A
62. If you ride your bike at an average speed of 4 km/h and need to travel a total distance of 28 km, how long will
it take you to reach your destination? Show your work.
63. A tow truck exerts a net horizontal force of 1050 N on an 760-kilogram car. What is the acceleration of the
car during this time? Show your work.
64. The mass of a newborn baby is 3.5 kilograms. What is the baby’s weight? (The acceleration due to gravity at
Earth’s surface is 9.8 m/s2.) Show your work.
Essay
65. Explain how velocity is different from speed.
66. Picture a ball traveling at a constant speed around the inside of a circular structure. Is the ball accelerating?
Explain your answer.
Other
USING SCIENCE SKILLS
Figure 11-2
67. Using Tables and Graphs Which graph in Figure 11-2 shows periods of constant speed? Explain your
answer.
68. Interpreting Graphics Look at Figure 11-2. Describe the motion of the object in Graph A.
69. Using Models Which graph in Figure 11-2 shows acceleration? How do you know?
70. Calculating Using Graph A in Figure 11-2, calculate the average speed of the object in motion from 12 s to
20 s. Explain your calculation.
71. Comparing and Contrasting Compare Graphs A and B in Figure 11-2. At a time of 2 seconds, which graph
shows a greater velocity? How do you know?
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