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Transcript
2012 - 2013 Study Guide
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. Tides are caused by
a. differences in the gravitational force of the sun at different points on Earth.
b. differences in the gravitational force of the moon at different points on Earth.
c. differences in Earth’s gravitational field strength at different points on Earth’s surface.
d. fluctuations in the gravitational attraction between Earth and the moon.
____
2. Why does an astronaut weigh less on the moon than on Earth?
a. The astronaut has less mass on the moon.
b. The astronaut is farther from Earth’s center when he or she is on the moon.
c. The gravitational field strength is less on the moon’s surface than on Earth’s surface.
d. The astronaut is continually in free fall because the moon orbits Earth.
____
3. If you lift an apple from the ground to some point above the ground, the gravitational potential energy in the
system increases. This potential energy is stored in
a. the apple.
b. Earth.
c. both the apple and Earth.
d. the gravitational field between Earth and the apple.
____
4. In this text, which of the following symbols represents gravitational field strength?
a. F
c. g
b. G
____
5. In this text, which of the following symbols represents the constant of universal gravitation?
a. F
c. g
b. G
____
d. F
d. F
6. Which of the following equations expresses Newton’s law of universal gravitation?
a.
c.
b.
d.
____
7. When calculating the gravitational force between two extended bodies, you should measure the distance
a. from the closest points on each body.
b. from the most distant points on each body.
c. from the center of each body.
d. from the center of one body to the closest point on the other body.
____
8. The gravitational force between two masses is 36 N. What is the gravitational force if the distance between them
is tripled? (G = 6.673  10
Nm /kg )
a. 4.0 N
c. 18 N
b. 9.0 N
d. 27 N
____
9. Two small masses that are 10.0 cm apart attract each other with a force of 10.0 N. When they are 5.0 cm apart,
these masses will attract each other with what force?
(G = 6.673  10
Nm /kg )
a. 5.0 N
c. 20.0 N
b. 2.5 N
d. 40.0 N
____ 10. Until the middle of the 16th century, most people believed ____ was at the center of the universe.
a. Earth
c. the sun
b. the moon
d. a black hole
____ 11. If you cannot exert enough force to loosen a bolt with a wrench, which of the following should you do?
a. Use a wrench with a longer handle.
b. Tie a rope to the end of the wrench and pull on the rope.
c. Use a wrench with a shorter handle.
d. You should exert a force on the wrench closer to the bolt.
____ 12. A heavy bank-vault door is opened by the application of a force of 3.0  10 N directed perpendicular to the
plane of the door at a distance of 0.80 m from the hinges. What is the torque?
a. 120 Nm
c. 300 Nm
b. 240 Nm
d. 360 Nm
____ 13. If the torque required to loosen a nut on a wheel has a magnitude of 40.0 Nm and the force exerted by a
mechanic is 133 N, how far from the nut must the mechanic apply the force?
a. 1.20 m
c. 30.1 cm
b. 15.0 cm
d. 60.2 cm
____ 14. Which of the following is the equation for average velocity?
a.
c. v
= xt
b.
d.
____ 15. Which of the following units is the SI unit of velocity?
a. meter
c. meter per second
b. metersecond
d. second per meter
____ 16. In the graph above, a toy car rolls from +3 m to +5 m. Which of the following statements is true?
a. xf = +3 m
c. x = +3 m
b. xi = +3 m
d. vavg = 3 m/s
____ 17. Suppose you are given a position versus time graph. The slope of a line drawn tangent to a point on the curve of
this graph describes what quantity?
a. acceleration
c. instantaneous velocity
b. displacement
d. position
____ 18. According to the graph above, the cat has the fastest speed during which interval?
a. 0.0–5.0 s
c. 10.0–15.0 s
b. 5.0–10.0 s
d. 15.0–20.0 s
____ 19. Which of the following line segments on a position versus time graph is physically impossible?
a. a horizontal line
c. a straight line that slopes to the right
b. a straight line that slopes to the left
d. a vertical line
____ 20. Acceleration is defined as
a. a rate of displacement.
b. the rate of change of displacement.
c. the change in velocity.
d. the rate of change of velocity.
____ 21. Which of the following is the equation for acceleration?
a.
c. a = vt
b.
d.
____ 22. If you know the acceleration of a car, its initial velocity, and the time interval, which of the following can you
predict?
a. the direction of the car’s final velocity
b. the magnitude of the car’s final velocity
c. the displacement of the car
d. all of the above
____ 23. In the figure above, which diagram represents the vector addition C = A + B?
a. I
c. III
b. II
d. IV
____ 24. In the figure above, which diagram represents the vector subtraction C = A–B?
a. I
c. III
b. II
d. IV
____ 25. An ant on a picnic table travels 3.0  10 cm eastward, then 25 cm northward, and finally 15 cm westward.
What is the magnitude of the ant’s displacement relative to its original position?
a. 70 cm
c. 52 cm
b. 57 cm
d. 29 cm
____ 26. Which of the following is the motion of objects moving in two dimensions under the influence of gravity?
a. horizontal velocity
c. vertical velocity
b. directrix
d. projectile motion
____ 27. Which of the following is an example of projectile motion?
a. a jet lifting off a runway
b. a thrown baseball
c. an aluminum can dropped straight down into the recycling bin
d. a space shuttle being launched
The figure above shows the path of a ball tossed from a building. Air resistance is ignored.
____ 28. At what point of the ball’s path shown in the figure above is the vertical component of the ball’s velocity zero?
a. A
c. C
b. B
d. D
____ 29. In the figure above, the horizontal component of the ball’s velocity at A is
a. zero.
b. equal to the vertical component of the ball’s velocity at C.
c. equal in magnitude but opposite in direction to the horizontal component of the ball’s
velocity at D.
d. equal to the horizontal component of its initial velocity.
____ 30. Which of the following is the cause of an acceleration?
a. speed
c. force
b. inertia
d. velocity
____ 31. What causes a moving object to change direction?
a. acceleration
c. inertia
b. velocity
d. force
____ 32. A newton is equivalent to which of the following quantities?
a. kg
c. kgm/s
b. kgm/s
d. kg(m/s)
____ 33. A free-body diagram represents all of the following except
a. the object.
c. forces exerted by the object.
b. forces as vectors.
d. forces exerted on the object.
____ 34. The free-body diagram shown above represents a car being pulled by a towing cable. In the diagram, the 5800 N
force is
a. the gravitational force acting on the car.
b. the backward force the road exerts on the car.
c. the upward force the road exerts on the car.
d. the force exerted by the towing cable on the car.
____ 35. 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.
____ 36. Which of the following is the tendency of an object to maintain its state of motion?
a. acceleration
c. force
b. inertia
d. velocity
____ 37. 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
____ 38. A car goes forward along a level road at constant velocity. The additional force needed to bring the car into
equilibrium is
a. greater than the normal force times the coefficient of static friction.
b. equal to the normal force times the coefficient of static friction.
c. the normal force times the coefficient of kinetic friction.
d. zero.
____ 39. If a nonzero net force is acting on an object, then the object is definitely
a. at rest.
c. being accelerated.
b. moving with a constant velocity.
d. losing mass.
____ 40. Which statement about the acceleration of an object is correct?
a. The acceleration of an object is directly proportional to the net external force acting on the
object and inversely proportional to the mass of the object.
b. The acceleration of an object is directly proportional to the net external force acting on the
object and directly proportional to the mass of the object.
c. The acceleration of an object is inversely proportional to the net external force acting on the
object and inversely proportional to the mass of the object.
d. The acceleration of an object is inversely proportional to the net external force acting on the
object and directly proportional to the mass of the object.
____ 41. 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?
a. 0.22 m/s
c. 3.2 m/s
b. 0.69 m/s
d. 4.6 m/s
____ 42. The statement by Newton that for every action there is an equal but opposite reaction is which of his laws of
motion?
a. first
c. third
b. second
d. fourth
____ 43. Newton’s third law of motion involves the interactions of
a. one object and one force.
c. two object and one force.
b. one object and two forces.
d. two objects and two forces.
____ 44. A measure of the quantity of matter is
a. density.
b. weight.
c. force.
d. mass.
____ 45. 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.
____ 46. 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.
____ 47. What is the common formula for work? Assume that W is the work, F is a constant force, v is the change in
velocity, and d is the displacement.
a. W = Fv
c. W = Fd
b. W = Fd
d. W = F d
____ 48. 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
____ 49. A construction worker pushes a wheelbarrow 5.0 m with a horizontal force of 50.0 N. How much work is done
by the worker on the wheelbarrow?
a. 10 J
c. 250 J
b. 55 J
d. 1250 J
____ 50. 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.
____ 51. Gravitational potential energy is always measured in relation to
a. kinetic energy.
c. total potential energy.
b. mechanical energy.
d. a zero level.
____ 52. 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.
____ 53. Which of the following is the rate at which energy is transferred?
a. potential energy
c. mechanical energy
b. kinetic energy
d. power
____ 54. How much power is required to lift a 2.0 kg mass at a speed of 2.0 m/s?
a. 2.0 J
c. 9.8 J
b. 4.0 J
d. 39 J
____ 55. Which of the following equations can be used to directly calculate an object’s momentum, p?
a. p = mv
c. p = Ft
b.
d. p = Ft
____ 56. What are the SI units for momentum?
a. Nm
b. J
c. kgm/s
d. kgm/s
____ 57. When comparing the momentum of two moving objects, which of the following is correct?
a. The object with the higher velocity will have less momentum if the masses are equal.
b. The more massive object will have less momentum if its velocity is greater.
c. The less massive object will have less momentum if the velocities are the same.
d. The more massive object will have less momentum if the velocities are the same.
____ 58. A person sitting in a chair with wheels stands up, causing the chair to roll backward across the floor. The
momentum of the chair
a. was zero while stationary and increased when the person stood.
b. was greatest while the person sat in the chair.
c. remained the same.
d. was zero when the person got out of the chair and increased while the person sat.
____ 59. If a force is exerted on an object, which statement is true?
a. A large force always produces a large change in the object’s momentum.
b. A large force produces a large change in the object’s momentum only if the force is applied
over a very short time interval.
c. A small force applied over a long time interval can produce a large change in the object’s
momentum.
d. A small force always produces a large change in the object’s momentum.
____ 60. The impulse experienced by a body is equivalent to the body’s change in
a. velocity.
c. momentum.
b. kinetic energy.
d. force.
____ 61. A 20 kg shopping cart moving at a velocity of 0.5 m/s collides with a store wall and stops. The momentum of the
shopping cart
a. increases.
c. remains the same.
b. decreases.
d. is conserved.
____ 62. A soccer ball collides with another soccer ball at rest. The total momentum of the balls
a. is zero.
c. remains constant.
b. increases.
d. decreases.
____ 63. The law of conservation of momentum states that
a. the total initial momentum of all objects interacting with one another usually equals the total
final momentum.
b. the total initial momentum of all objects interacting with one another does not equal the total
final momentum.
c. the total momentum of all objects interacting with one another is zero.
d. the total momentum of all objects interacting with one another remains constant regardless
of the nature of the forces between the objects.
____ 64. For a system in simple harmonic motion, which of the following is the time required to complete a cycle of
motion?
a. amplitude
c. frequency
b. period
d. revolution
____ 65. For a system in simple harmonic motion, which of the following is the number of cycles or vibrations per unit of
time?
a. amplitude
c. frequency
b. period
d. revolution
____ 66. How are frequency and period related in simple harmonic motion?
a. They are directly related.
b. They are inversely related.
c. Their sum is constant.
d. Both measure the number of cycles per unit of time.
____ 67. By what factor should the length of a simple pendulum be changed in order to triple the period of vibration?
a. 3
c. 9
b. 6
d. 27
____ 68. A repelling force occurs between two charged objects when the charges are of
a. unlike signs.
c. equal magnitude.
b. like signs.
d. unequal magnitude.
____ 69. When a glass rod is rubbed with silk and becomes positively charged,
a. electrons are removed from the rod.
c. protons are added to the silk.
b. protons are removed from the silk.
d. the silk remains neutral.
____ 70. Electric charge is
a. found only in a conductor.
b. conserved.
c. found only in insulators.
d. not conserved.
____ 71. Charge is most easily transferred in
a. nonconductors.
c. semiconductors.
b. conductors.
d. insulators.
____ 72. In the diagram shown above, the circles represent small balls that have electric charges. Ball 1 has a negative
charge, and ball 2 is repelled by ball 1. Next, you see that ball 2 repels ball 3 and that ball 3 attracts ball 4. What
is the electric charge on ball 4?
a. Ball 4 may have either a positive or negative charge.
b. Ball 4 has a negative charge.
c. Ball 4 has a positive charge.
d. It is not possible to determine the charge on ball 4.
____ 73. Which statement is the most correct regarding electric insulators?
a. Charges within electric insulators do not readily move.
b. Electric insulators have high tensile strength.
c. Electric charges move freely in electric insulators.
d. Electric insulators are good heat conductors.
____ 74. Conductors can be charged by ____, while insulators cannot.
a. grounding
c. polarization
b. induction
d. contact
____ 75. Two point charges, initially 2 cm apart, are moved to a distance of 10 cm apart. By what factor does the
resulting electric force between them change?
a. 25
c.
b. 5
d.
____ 76. If the charge is tripled for two identical charges maintained at a constant separation, the electric force between
them will be changed by what factor?
a.
c. 9
b.
d. 18
____ 77. What occurs when two charges are moved closer together?
a. The electric field doubles.
b. Coulomb’s law takes effect.
c. The total charge increases.
d. The force between the charges increases.
____ 78. Which of the following is the best description of a schematic diagram?
a.
b.
c.
d.
uses pictures to represent the parts of a circuit
determines the location of the parts of a circuit
shows the parts of a circuit and how the parts connect to each other
shows some of the parts that make up a circuit
____ 79.
What happens when the switch is closed in the circuit shown above?
a. The lamp lights because current from the battery flows through the lamp.
b. Current from the battery is carried through the resistor.
c. Current from the battery is carried through both the lamp and the resistor.
d. The lamp goes out, because the battery terminals connect to each other.
____ 80. If the batteries in a portable CD player provide a terminal voltage of 12 V, what is the potential difference across
the entire CD player?
a. 3.0 V
c. 6.0 V
b. 4.0 V
d. 12 V
____ 81. Three resistors with values of 4.0 , 6.0 , and 8.0 , respectively, are connected in series. What is their
equivalent resistance?
a. 18 
c. 6.0 
b. 8.0 
d. 1.8 
____ 82. Three resistors connected in series carry currents labeled I , I , and I , respectively. Which of the following
expresses the total current, I , in the system made up of the three resistors in series?
a. It = I1 + I2 + I3
c. It = I1 = I2 = I3
b.
d.
It =
It =
____ 83. Three resistors connected in series have potential differences across them labeled V , V , and V . Which of
the following expresses the potential difference taken over the three resistors together?
a. Vt = V1 + V2 + V3
c. Vt = V1 = V2 = V3
b.
d.
Vt =
Vt =
____ 84. Three resistors with values of R , R , and R are connected in series. Which of the following expresses the total
resistance, R , of the three resistors?
a. Req = R1 + R2 + R3
b.
Req =
c. Req = R1 = R2 = R3
d.
Req =
____ 85. Three resistors with values of 3.0 , 6.0 , and 12  are connected in series. What is the equivalent resistance
of this combination?
a. 0.58 
c. 7.0 
b. 1.7 
d. 21 
____ 86. Three resistors connected in parallel carry currents labeled I , I , and I . Which of the following expresses the
total current I in the combined system?
a. It = I1 + I2 + I3
c. It = I1 = I2 = I3
b.
d.
It =
It =
____ 87. Three resistors with values of R , R , and R are connected in parallel. Which of the following expresses the
total resistance, R , of the three resistors?
a. Req = R1 + R2 + R3
b.
Req =
c. Req = R1 = R2 = R3
d.
Req =
____ 88. Two resistors having the same resistance value are wired in parallel. How does the equivalent resistance
compare to the resistance value of a single resistor?
a. The equivalent resistance is twice the value of a single resistor.
b. The equivalent resistance is the same as a single resistor.
c. The equivalent resistance is half the value of a single resistor.
d. The equivalent resistance is greater than that of a single resistor.
____ 89. Three resistors with values of 4.0 , 6.0 , and 10.0  are connected in parallel. What is their equivalent
resistance?
a. 20.0 
c. 6.0 
b. 7.3 
d. 1.9 
____ 90. Two resistors with values of 6.0  and 12  are connected in parallel. This combination is connected in series
with a 4.0  resistor. What is the equivalent resistance of this combination?
a. 0.50 
c. 8.0 
b. 2.0 
d. 22 
____ 91. Two resistors with values of 6.0  and 12  are connected in parallel. This combination is connected in series
with a 2.0  resistor and a 24 V battery. What is the current in the 2.0  resistor?
a. 2.0 A
c. 6.0 A
b. 4.0 A
d. 12 A
____ 92. Which of the following situations is not true for magnets?
a.
b.
c.
d.
Like poles repel each other.
Unlike poles repel each other.
North poles repel each other.
A north pole and a south pole will attract each other.
____ 93. Where is the magnitude of the magnetic field around a permanent magnet greatest?
a. The magnitude is greatest close to the poles.
b. The magnitude is greatest far from the poles.
c. The magnitude is equal at all points on the field.
d. The magnitude is greatest halfway between poles.
____ 94. All of the following statements about magnetic field lines around a permanent magnet are true except which
one?
a. Magnetic field lines appear to end at the north pole of a magnet.
b. Magnetic field lines have no beginning or end.
c. Magnetic field lines always form a closed loop.
d. In a permanent magnet, the field lines actually continue within the magnet itself.
____ 95. Which compass needle orientation in the figure above might correctly describe the magnet’s field at that point?
a. a
c. c
b. b
d. d
____ 96. A microscopic magnetic region composed of a group of atoms whose magnetic fields are aligned in a common
direction is called a(n) ____. In most materials, when these groups are randomly distributed, the substance will
show ____ no magnetism.
a. domain; no
c. cell; unusual
b. pole; some
d. ion; strong
____ 97. In a magnetized substance, the domains
a. are randomly oriented.
b. cancel each other.
c. line up mainly in one direction.
d. can never be reoriented.
____ 98. In soft magnetic materials such as iron, what happens when an external magnetic field is removed?
a. The domain alignment persists.
b. The orientation of domains fluctuates.
c. The material becomes a hard magnetic material.
d. The material returns to an unmagnetized state.
____ 99. A current in a long, straight wire produces a magnetic field. These magnetic field lines
a. radiate out from the wire to infinity.
b. come in from infinity to the wire.
c. form circles that pass through the wire.
d. form circles that go around the wire.
____ 100. According to the right-hand rule, if a current-carrying wire is grasped in the right hand with the thumb in the
direction of the current, the four fingers will curl in the direction of
a. the magnetic force,
c. the current’s velocity, .
.
b. the magnetic field,
.
d. the current’s path, .
____ 101. The lines of the magnetic field around a current-carrying wire
a. point away from the wire.
b. point toward the wire.
c. form concentric circles around the wire.
d. are parallel with the wire.
____ 102. An electron moves north at a velocity of 4.5  10 m/s and has a magnetic force of 7.2  10
If the magnetic field points upward, what is the magnitude of the magnetic field?
a. 1.0 mT
c. 3.6 mT
b. 2.0 mT
d. 4.8 mT
N exerted on it.
____ 103. If a proton is released at the equator and falls toward Earth under the influence of gravity, the magnetic force on
the proton will be toward the ____ assuming the magnetic field is directed toward the north at this location.
a. north
c. east
b. south
d. west
____ 104. A stationary positive charge, Q, is located in a magnetic field, B, which is directed toward the right. What is the
direction of the magnetic force on Q?
a. toward the right
c. down
b. up
d. There is no magnetic force.
____ 105. A race car accelerates from 0.0 m/s to 51.0 m/s with a displacement of 75.0 m. What is the car’s acceleration?
a. 12.5 m/s
b. 19.2 m/s
c. 17.3 m/s
d. 15.8 m/s
____ 106. A rock is thrown downward from the top of a cliff with an initial speed of 13 m/s. If the rock hits the ground after 2.7 s,
what is the height of the cliff? (Disregard air resistance.)
a. 37.4 m
b. 70.8 m
c. 112.5 m
d. 89.0 m
____ 107. A rock is thrown straight upward with an initial velocity of 25.4 m/s where the acceleration due to gravity has a magnitude
of 9.81 m/s2. What is the rock’s displacement after 2.65 s?
a. 25.4 m
b. 32.9 m
c. 39.2 m
d. 52.4 m
____ 108. Compare the momentum of a 5450 kg truck moving at 8.00 m/s to the momentum of a 2725 kg car moving at 16.0 m/s.
a. The truck’s momentum is larger.
b. The truck’s momentum is smaller.
c. They have the same momentum.
d. There isn’t enough information to
determine.
____ 109. What is the electric force between an electron and a proton that are separated by a distance of 3.4 x 10-10 m?
a. 7.62 x 10-8 N
b. 4.36 x 10-9 N
c. 1.99 x 10-9 N
d. 8.74 x 10-10 N
____ 110. A wire 76 m long carries a current of 17 A from west to east. If a magnetic field of 7.5 x 10 -4 T directed toward the south is
acting on the wire, find the direction and magnitude of the magnetic force.
a. 0.97 N down
b. 0.97 N up
c. 5.8 x 10-7 N down
d. 5.8 x 10-7 N up
____ 111. The magnetic force on a straight wire 0.69 m long is 1.5 x 10-3 N. The current in the wire is 16.9 A. What is the magnitude
of the magnetic field that is perpendicular to the wire?
a. 3.1 x 10-4 T
b. 9.4 x 10-3 T
c. 6.7 x 10-5 T
d. 1.3 x 10-4 T
____ 112. A boulder sits on a cliff 42 m above the floor of the canyon. If the boulder’s mass is 79 kg. what is the potential
energy of the boulder?
a. 3.25 x 104 J
b. 3318 J
c. 774.2 J
d. 1.87 x 103 J
____ 113. A boulder sits on a cliff 42 m above the floor of the canyon. If the boulder’s mass is 79 kg and it fell, what
would be it’s velocity as it hit the ground?
a. 57.4 m/s
c. 28.7 m/s
b. 25.9 m/s
d. 14.3 m/s