**C1 Electric Circuits (Current, Resistance, Power)
Chapter 17
**

**On-Line Quiz - 300 points
**

**25 questions worth 12 points each**

51. Electric
resistance has units of:

a. ohm

b. (W-m)^{-1}

c. ampere

d. volt-ampere

e. (^{o}C)^{
-1}

f. W-m

52. Conductivity
has units of:

a. ohm

b. (W-m)^{ -1}

c. ampere

d. volt-ampere

e. (^{o}C)^{
-1}

f. W-m

53. Temperature
coefficient of resistivity has units of:

a. ohm

b. (W-m)^{ -1}

c. ampere

d. volt-ampere

e. (^{o}C)^{
-1}

f. W-m

54. Electric
current has units of:

a. ohm

b. (W-m)^{ -1}

c. ampere

d. volt-ampere

e. (^{o}C)^{
-1}

f. W-m

55. Resistivity
has units of:

a. ohm

b. (W-m)^{ -1}

c. ampere

d. volt-ampere

e. (^{o}C)^{
-1}

f. W-m

56. Electric
power has units of:

a. ohm

b. (W-m)^{ -1}

c. ampere

d. volt-ampere

e. (^{o}C)^{
-1}

f. W-m

57. A
car battery

a. has an emf of 6 V consisting of
one 6-V cell.

b. has an emf of 6 V consisting of
three 2-V cells connected in series.

c. has an emf of 6 V consisting of
three 2-V cells connected in parallel.

d. has an emf of 12 V consisting of
six 2-V cells connected in series.

e. has an emf of 12 V consisting of
six 2-V cells connected in parallel.

58. If
you connect two identical storage batteries together in parallel, and place them
in a circuit, the combination will provide

a. twice the voltage and twice the
total charge that one battery would.

b. twice the voltage and the same
total charge that one battery would.

c. the same voltage and twice the
total charge that one battery would.

d. half the voltage and half the
total charge that one battery would.

e. half the voltage and twice the
total charge that one battery would.

59. If
you connect two identical storage batteries together in series ("+" to
"-"), and place them in a circuit, the combination will provide

a. zero volts.

b. twice the voltage, and different
currents will flow through each.

c. twice the voltage, and the same
current will flow through each.

d. the same voltage, and different
currents will flow through each.

e. the same voltage and the same
current will flow through each.

60. The
net direction in which electrons flow through a circuit is

a. the conventional current

b. opposite the conventional current

61. A
coulomb per second is the same as

a. a watt.

b. an ampere.

c. a volt-second.

d. a volt per second.

62. A
device obeying Ohm's law must have a resistance which

a. is proportional to voltage

b. is proportional to current

c. is constant

d. is zero

63. Consider
two copper wires. One has twice the
length and twice the cross-sectional area of the other.
How do the resistances of these two wires compare?

a. Both wires have the same
resistance.

b. The longer wire has twice the
resistance of the shorter wire.

c. The longer wire has four times
the resistance of the shorter wire.

d. None of the above.

64. Negative
temperature coefficients of resistivity

a. do not exist.

b. exist in conductors.

c. exist in semiconductors.

d. exist in superconductors.

65. Which
of the above graphs indicates that the material is likely a semiconductor?

a. graph A

b. graph B

c. graph C

d. graph D

66. If
the resistance in a constant voltage circuit is doubled, the power dissipated by
that circuit will

a. increase by a factor of two.

b. increase by a factor of four.

c. decrease to one-half its original
value.

d. decrease to one-fourth its
original value.

67. The
resistivity of most common metals

a. remains constant over wide
temperature ranges.

b. increases as the temperature
increases.

c. decreases as the temperature
increases.

d. varies randomly as the
temperature increases.

68. In
the graph shown, what physical quantity does the slope represent?

a. Current

b. Energy

c. Resistivity

d. Resistance

69. A
500-W device is connected to a 100-V power source.
What current flows through this source?

a. 50,000 A

b. 0.2 A

c. 5 A

d. None of the above

70. A
lamp uses a 150-W bulb. If it is
used at 120 V, what current does it draw and what is its resistance?

71. Appliances
in the USA are designed to work on 110-120 V, whereas appliances in Europe
operate on 220-240 V. What would
happen if you tried to use a European electric shaver in this country?

a. It would probably work as well as
it does in Europe, since it is the power rating, not the voltage rating, that
matters.

b. It would probably work as well as
it does in Europe, since it is the current rating, not the voltage rating, that
matters.

c. It would barely work (or maybe
not work at all), since the voltage here is too low to push enough current
through the device.

d. It would probably overheat and
burn up before very long.

e. This question cannot be answered
without knowing the frequency used in Europe and in the USA, since this is the
parameter that matters most in any electrical device that operates on
alternating current.

72. A
battery acquires and stores:

a. charge

b. potential

c. energy

d. all of the above

73. What
do you buy from the "power" company?

a. power

b. potential

c. current

d. energy

74. A
negative charge, if free, tries to move

a. from high potential to low
potential

b. from low potential to high
potential

c. toward infinity

d. away from infinity

75. Consider
a current moving from left to right through a resistor. Which end of the resistor is at higher potential?

a. left

b. right

c. indeterminate depends if current
is charging a battery or discharging a battery.