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Name: ________________________ Class: ___________________ Date: __________
ID: A
Energy Pretest
Multiple Choice
Identify the choice that best completes the statement or answers the question.
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1. In which of the following sentences is work used in the scientific sense of the word?
a. Holding a heavy box requires a lot of work.
b. A scientist works on an experiment in the laboratory.
c. Sam and Rachel pushed hard, but they could do no work on the car.
d. John learned that shoveling snow is hard work.
2. In which of the following sentences is work used in the everyday sense of the word?
a. Lifting a heavy bucket involves doing work on the bucket.
b. The force of friction usually does negative work.
c. Sam and Rachel worked hard pushing the car.
d. Work is a physical quantity.
3. A force does work on an object if a component of the force
a. is perpendicular to the displacement of the object.
b. is parallel to the displacement of the object.
c. perpendicular to the displacement of the object moves the object along a path that returns
the object to its starting position.
d. parallel to the displacement of the object moves the object along a path that returns the
object to its starting position.
4. Work is done when
a. the displacement is not zero.
b. the displacement is zero.
c. the force is zero.
d. the force and displacement are perpendicular.
5. What is the common formula for work? Assume that W is the work, F is a constant force, Dv is the change in
velocity, and d is the displacement.
a.
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W = FDv
c.
W = Fd 2
b. W = Fd
d. W = F 2 d
6. In which of the following scenarios is work done?
a. A weightlifter holds a barbell overhead for 2.5 s.
b. A construction worker carries a heavy beam while walking at constant speed along a flat
surface.
c. A car decelerates while traveling on a flat stretch of road.
d. A student holds a spring in a compressed position.
7. In which of the following scenarios is no net work done?
a. A car accelerates down a hill.
b. A car travels at constant speed on a flat road.
c. A car decelerates on a flat road.
d. A car decelerates as it travels up a hill.
8. Which of the following energy forms is associated with an object in motion?
a. potential energy
c. nonmechanical energy
b. elastic potential energy
d. kinetic energy
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Name: ________________________
ID: A
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9. Which of the following energy forms is associated with an object due to its position?
a. potential energy
c. total energy
b. positional energy
d. kinetic energy
____ 10. Which of the following energy forms is not involved in hitting a tennis ball?
a. kinetic energy
c. gravitational potential energy
b. chemical potential energy
d. elastic potential energy
____ 11. Which of the following formulas would be used to directly calculate the kinetic energy of an object with mass m
bouncing up and down on a spring with spring constant k?
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a. KE = 2 kx 2
c. KE = 2 mv 2
b.
KE = - 2 kx 2
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d.
KE = - 2 mv 2
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____ 12. Which of the following equations expresses the work-kinetic energy theorem?
a. ME i = ME f
c. DW = DKE
b.
W net = DPE
d.
W net = DKE
____ 13. The main difference between kinetic energy and potential energy is that
a. kinetic energy involves position, and potential energy involves motion.
b. kinetic energy involves motion, and potential energy involves position.
c. although both energies involve motion, only kinetic energy involves position.
d. although both energies involve position, only potential energy involves motion.
____ 14. Which form of energy is involved in weighing fruit on a spring scale?
a. kinetic energy
c. gravitational potential energy
b. nonmechanical energy
d. elastic potential energy
____ 15. Gravitational potential energy is always measured in relation to
a. kinetic energy.
c. total potential energy.
b. mechanical energy.
d. a zero level.
____ 16. What are the units for a spring constant?
a. N
c. N·m
b. m
d. N/m
____ 17. Which of the following is a true statement about the conservation of energy?
a. Potential energy is always conserved.
b. Kinetic energy is always conserved.
c. Mechanical energy is always conserved.
d. Total energy is always conserved.
____ 18. In the presence of frictional force,
a. nonmechanical energy is negligible and mechanical energy is no longer conserved.
b. nonmechanical energy is negligible and mechanical energy is conserved.
c. nonmechanical energy is no longer negligible and mechanical energy is conserved.
d. nonmechanical energy is no longer negligible and mechanical energy is no longer
conserved.
____ 19. Which of the following refers to the sum of kinetic energy and all forms of potential energy?
a. total energy
c. nonmechanical energy
b. S energy
d. mechanical energy
____ 20. Which of the following are examples of conservable quantities?
a. potential energy and length
c. mechanical energy and mass
b. mechanical energy and length
d. kinetic energy and mass
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Name: ________________________
ID: A
____ 21. Which of the following is a form of mechanical energy?
a. internal energy
c. gravitational potential energy
b. chemical potential energy
d. electrical energy
____ 22. Friction converts kinetic energy to
a. mechanical energy.
c. nonmechanical energy.
b. potential energy.
d. total energy.
____ 23. Which of the following is the rate at which energy is transferred?
a. potential energy
c. mechanical energy
b. kinetic energy
d. power
____ 24. Which of the following is the rate at which work is done?
a. potential energy
c. mechanical energy
b. kinetic energy
d. power
____ 25. Which of the following equations is not an equation for power, P, in terms of work, W, displacement, d, time
interval, Dt, force, F, and/or velocity, v?
d
a. P = F
c. P = Fv
Dt
W
Fv
b. P =
d. P =
Dt
Dt
____ 26. Which of the following are not units of power?
a. hp
c. W
b. J
d. J/s
____ 27. A more powerful motor can do
a. more work in a longer time interval.
b. the same work in a shorter time interval.
c. less work in a longer time interval.
d. the same work in a longer time interval.
____ 28. If the sign of work is negative,
a. the displacement is perpendicular to the force.
b. the displacement is in the direction opposite the force.
c. the displacement is in the same direction as the force.
d. no work is done.
____ 29. A child moving at constant velocity carries a 2 N ice-cream cone 1 m across a level surface. What is the net
work done on the ice-cream cone?
a. 0 J
c. 2 J
b. 0.5 J
d. 20 J
____ 30. A worker does 25 J of work lifting a bucket, then sets the bucket back down in the same place. What is the total
net work done on the bucket?
a. –25 J
c. 25 J
b. 0 J
d. 50 J
____ 31. Ball A has triple the mass and speed of ball B. What is the ratio of the kinetic energy of ball A to ball B.
a. 3
c. 9
b. 6
d. 27
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Name: ________________________
ID: A
____ 32. If friction is the only force acting on an object during a given physical process, which of the following
assumptions can be made in regard to the object’s kinetic energy?
a. The kinetic energy decreases.
b. The kinetic energy increases.
c. The kinetic energy remains constant.
d. The kinetic energy decreases and then increases.
____ 33. The equation for determining gravitational potential energy is PE g = mgh. Which factor(s) in this equation is
____ 34.
____ 35.
____ 36.
____ 37.
____ 38.
____ 39.
____ 40.
(are) not intrinsic to an object?
a. m
c. h
b. g
d. both g and h
Which of the following parameters does not depend on how resistant a spring is to being compressed or
stretched?
a. compression distance
c. spring constant
b. relaxed length
d. stretching distance
If the displacement of a horizontal mass-spring system was doubled, the elastic potential energy in the system
would change by a factor of
a. 1/4.
c. 2.
b. 1/2.
d. 4.
If the mass in a horizontal mass-spring system was doubled, the elastic potential energy in the system would
change by a factor of
a. 0 (no change).
c. 2.
b. 1/2.
d. 4.
Why doesn’t the principle of mechanical energy conservation hold in situations when frictional forces are
present?
a. Kinetic energy is not completely converted to a form of potential energy.
b. Potential energy is completely converted to a form of gravitational energy.
c. Chemical energy is not completely converted to electrical energy.
d. Kinetic energy is completely converted to a form of gravitational energy.
For which of the following situations is the conservation of mechanical energy most likely to be a valid
assumption?
a. A skateboard rolls across a sewer grate.
b. A parachutist falls from a plane.
c. You rub your hands together to keep warm.
d. A soccer ball flies through the air.
Energy that is stored due to the position of an object may be called ____ energy.
a. kinetic
b. potential
c. radiant
d. nuclear
A 20-kilogram object falls 2.0 meters to the floor. At what point in its fall does the kinetic energy of a body
equal its potential energy?
a. At all points of the fall
b. Very nearly at the top of the fall
c. Halfway to the floor
d. Just the instant before it hits the floor
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Name: ________________________
ID: A
____ 41. An object falls without friction near Earth’s surface. The loss of its potential energy is equal to its:
a. loss of height.
b. loss of mass.
c. gain in kinetic energy.
d. gain in velocity.
____ 42. The diagram below represents a cart traveling from left to right along a frictionless surface with an initial speed
of 3 m/sec. At what point is the potential energy least?
a. A
b. B
c. C
d. D
____ 43. Work may be measured using units of:
a. watts.
b. newtons.
c. joules.
d. newtons per second.
____ 44. In science, work is defined as:
a. the mass of an object multiplied by its acceleration.
b. the mass of an object multiplied by the force required to move it.
c. force multiplied by the distance moved in a direction perpendicular to the force.
d. force multiplied by the distance moved in the same direction as the force.
____ 45. The metric unit for work is the:
a. newton.
b. joule.
c. watt.
d. meter.
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Name: ________________________
ID: A
____ 46. If forces A, B and C are equal, the work done by the forces as they are exerted on the box is:
____ 47.
____ 48.
____ 49.
____ 50.
____ 51.
a. greatest for force A.
b. greatest for force B.
c. greatest for force C.
d. the same for all forces.
A unit used to measure power is the:
a. joule.
b. newtons per second.
c. newton-meter.
d. watt.
Friction is a “catch-all” term for many processes that oppose:
a. heat.
b. wear.
c. motion.
d. None of the above
Potential energy increases as a marble:
a. slows rolling up an incline.
b. increases speed down an incline.
c. rolls at uniform speed on a level table.
d. sits motionless on the floor.
Calculate the work done to lift a barbell weighing 100 newtons a distance of 1.5 meters.
a. 0.015 joules
b. 15 joules
c. 66.7 joules
d. 150 joules
Jonah is pushing his younger sister, Jessica, on a swing. If Jessica weighs 350 newtons, how much higher
above the ground must Jonah push her to increase her potential energy by 525 joules?
a. 0.67 meters
b. 1.5 meters
c. 3.6 meters
d. 5.4 meters
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Name: ________________________
ID: A
____ 52. A basketball player who weighs 600 newtons jumps 0.5 meters vertically off the floor.What is her kinetic
energy the instant before hitting the floor?
a. 30 joules
b. 60 joules
c. 300 joules
d. 600 joules
____ 53. Lifting a 70-kilogram barbell 2.0 meters above the floor increases its potential energy by about:
a. 35 joules.
b. 140 joules.
c. 350 joules.
d. 1,400 joules.
____ 54. The amount of mechanical kinetic energy possessed by a 0.25-kilogram ball rolling at a speed of 2.5 meters per
second is ____ joules.
a. 0.31
b. 0.63
c. 0.78
d. 1.6
____ 55. As the speed of a moving object doubles, the amount of mechanical kinetic energy that it possesses:
a. increases by two times.
b. increases by four times.
c. decreases by two times.
d. decreases by four times.
____ 56. An automobile jack exerts a force of 4,500 newtons to raise a car 0.25 meters. The amount of work done by the
jack is about ____ joules.
a. 0.00056
b. 1,100
c. 4,500
d. 18,000
____ 57. A 2.2-kilogram crate is pulled by a 30-newton force over a distance of 5 meters. The work done by pulling the
crate is ____ joules.
a. 11
b. 66
c. 150
d. 330
____ 58. When a force applied to an object causes the object to move in the direction of the force, the object acquires:
a. energy.
b. mechanical advantage.
c. efficiency.
d. friction.
____ 59. Running up a flight of stairs, Maria generates 450 watts of power. If it takes her 6 seconds to go up the stairs,
the amount of work she does in running up the stairs is ____ joules.
a. 0.013
b. 75
c. 450
d. 2,700
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Name: ________________________
ID: A
____ 60. Jasmine, who weighs 400 newtons, moves up a 5.0-meter climbing wall in 15 seconds. The amount of power
generated by Jasmine as she climbs the wall is about ____ watts.
a. 130
b. 2,000
c. 6,000
d. 30,000
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ID: A
Energy Pretest
Answer Section
MULTIPLE CHOICE
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5-1.1
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ID: A
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intermediate
intermediate
intermediate
intermediate
intermediate
intermediate
intermediate
intermediate
intermediate
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section 3.2
section 3.2
section 3.2
section 3.2
section 3.2
section 3.2
section 4.1
section 4.1
section 4.1
section 4.3
section 3.2
section 3.2
section 3.2
section 3.2
section 3.2
section 3.2
section 3.2
section 4.1
section 4.1
section 4.1
section 4.1
section 4.1