Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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1.
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There
is a repulsive force between two charged objects when
a. charges
are of unlike sign. b. they have the same number of protons.
c. charges are of like sign. d. they have the same number of
electrons.
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2.
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There
is an attractive force between two charged objects when
a. charges
are of unlike sign. b. they have the same number of protons.
c. charges are of like sign. d. they have the same number of
electrons.
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3.
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When
a glass rod is rubbed with silk and becomes positively charged,
a. electrons are removed from the rod. b. protons are added to
the silk. c. protons are removed from the silk. d. the silk remains
neutral.
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4.
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The
electric force between charged objects is
a. attractive only. b. repulsive only.
c. either attractive or repulsive. d. neither attractive nor
repulsive.
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5.
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Electric force varies depending on the
a. charge
and distance between charged objects. b. charge and mass of charged
objects. c. height and mass of charged objects. d. mass and
distance between charged objects.
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6.
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Which
of the following is not true for both gravitational and electric
forces?
a. The inverse square distance law applies.
b. The force depends on a physical property of objects. c. Potential energy is
a function of the distance between objects. d. The force is either attractive or
repulsive.
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7.
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Every
charged particle produces
a. a negative charge. b. a positive
charge. c. a magnetic field. d. an electric field.
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8.
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The
electric field lines around a negatively charged particle
a. cross
positively charged particle field lines. b. cross negatively charged particle field
lines. c. always point inward. d. always point
outward.
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9.
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Electric field lines
a. point toward a negative charge.
b. point away from a positive charge. c. never cross one another.
d. all of the above.
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10.
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Electric field lines indicate
a. direction only. b. relative strength only.
c. both direction and relative strength. d. neither direction nor
strength.
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11.
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When
compared to a –2 charge, there are
a. an equal
number of field lines pointing inward toward a +4 charge. b. twice as many field
lines pointing inward toward a +4 charge. c. twice as many field lines pointing
outward from a +4 charge. d. half as many field lines pointing outward from a +4
charge.
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12.
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Potential difference is measured in
a. amperes. b. volts. c. coulombs.
d. joules.
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13.
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Which
of the following is not a type of electric cell?
a. electrochemical b. thermoelectric
c. mechanical d. photoelectric
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14.
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Batteries typically have
a. two
positive terminals. b. two negative terminals. c. one positive and
one negative terminal. d. no terminals.
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15.
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An
electric current is produced when charges are accelerated by an electric field to move to a position
of potential energy that is
a. higher. b. lower.
c. equal. d. infinite.
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16.
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Current is the rate at which charges move through a(n)
a. conductor. b. insulator.
c. voltage. d. joule.
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17.
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Potential differences cause
a. electrons to move from the positive terminal to the negative
terminal. b. electrons to move from the negative terminal to the positive
terminal. c. protons to move from the positive terminal to the negative
terminal. d. protons to move from the negative terminal to the positive
terminal.
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18.
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The
brightness of a light bulb is determined by its filament’s
a. voltage. b. amperes. c. watts.
d. resistance.
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19.
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Resistance is caused by
a. internal
friction. b. electron charge. c. proton charge.
d. a heat source.
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20.
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The
SI unit of resistance is the
a. volt. b. ampere.
c. ohm. d. joule.
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21.
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Whether or not charges will move in a material depends partly on how tightly ____ are
held in the atoms of the material.
a. electrons
b. neutrons c. protons d. resistors
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22.
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Which
of the following does not affect a material’s resistance?
a. length b. temperature c. the type of
material d. Ohm’s law
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23.
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A
flashlight bulb with a potential difference of 4.5 V across its filament has a power output of 8.0 W.
How much current is in the bulb filament?
a. 3.7
A b. 1.8 A c. 0.23 A d. 0.56 A
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24.
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What
is the potential difference across a resistor that dissipates 5.00 W of power and has a current of
5.0 A?
a. 1.0 V b. 125 V c. 4.00
V d. 0.20 V
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25.
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There
is a potential difference of 12 V across a resistor with 0.25 A of current in it. The resistance of
the resistor is
a. 48 W b. 24 W c. 12
W
d. 0.021 W
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26.
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A 13
W resistor has
0.050 A of current in it. What is the potential difference across the
resistor?
a. 6.5 V b. 0.65 V c. 0.065
V d. 0.0065 V
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27.
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A
resistor has a resistance of 280 W. How much current is in the resistor if there is a potential difference of 120 V
across the resistor?
a. 160 A b. 0.43 A c. 0.12
A d. 2.3 A
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28.
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A set
of electric trains are powered by a 9V battery. What is the resistance of the trains if they draw 3.0
A of current?
a. 3 W b. 0.03 W c. 27
W
d. 2.7 W
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29.
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The
resistance of an insulator is
a. absent. b. very
low. c. moderate. d. high.
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30.
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What
happens to the resistance of a superconductor when its temperature drops below the critical
temperature?
a. Resistance increases. b. Resistance
doubles. c. Resistance drops to zero. d. Resistance is reduced by
one-half.
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31.
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Which
of the following shows how conductors, insulators, superconductors, and semiconductors rank in order
of least resistance to most resistance?
a. superconductors, conductors, semiconductors, insulators
b. semiconductors, superconductors, conductors, insulators c. insulators,
conductors, semiconductors, superconductors d. none of the above
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32.
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Appliances connected so that they form a single pathway for charges to flow are
connected in a(n)
a. series circuit. b. parallel
circuit. c. open circuit. d. closed circuit.
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33.
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If a
lamp is measured to have a resistance of 45 W when it operates at a power of 80.0 W, what is the current in the
lamp?
a. 2.10 A b. 1.3 A c. 0.91
A d. 0.83 A
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34.
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An
electric toaster has a power rating of 1100 W at 110 V. What is the resistance of the heating
coil?
a. 7.5 W b. 9.0 W c. 10
W
d. 11 W
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35.
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If a
lamp is measured to have a resistance of 120 W when it operates at a power of 1.00 ×102 W, what is
the potential difference across the lamp?
a. 110
V b. 120 V c. 0.913 V d. 220 V
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36.
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If a
325 W heater has a current of 6.00 A, what is the resistance of the heating
element?
a. 88.1 W b. 54.2 W c. 9.03
W
d. 11.4 W
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37.
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A
color television draws about 2.5 A when it is connected to a 120 V outlet. Assuming electrical energy
costs $0.060 per kW·h, what is the cost of running the television for exactly 8
hours?
a. $1.44 b. $0.03
c. $0.14 d. $0.30
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38.
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A
microwave draws 5.0 A when it is connected to a 120 V outlet. If electrical energy cost
$0.090/kW·h, what is the cost of running the microwave for exactly 6
hours?
a. $2.70 b. $1.60
c. $0.72 d. $0.32
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39.
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What
happens to the overall resistance of a circuit when too many appliances are connected across a 120 V
outlet?
a. Resistance is increased. b. Resistance
remains the same. c. Resistance is decreased. d. Resistance is
zero.
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40.
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A
device that protects a circuit from current overload is called a(n)
a. resistor. b. capacitor. c. circuit
breaker. d. closed circuit.
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