Introduction to Electricity

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Introduction to Electricity
Chapter 17
Preview
CRCT Preparation
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CRCT Preparation
Chapter 17
1. The diagram shows four light bulbs wired in a
circuit. What would happen if bulb 3 burned
out? A Bulb 1 and bulb 2 would go out but bulb 4
will remain lit. B Bulb 2 and bulb 4 would go out
but bulb 1 will remain lit. C All of the other
bulbs would go out. D All of the other bulbs
would remain lit.
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CRCT Preparation
Chapter 17
1. The diagram shows four light bulbs wired in a
circuit. What would happen if bulb 3 burned
out? A Bulb 1 and bulb 2 would go out but bulb 4
will remain lit. B Bulb 2 and bulb 4 would go out
but bulb 1 will remain lit. C All of the other
bulbs would go out. D All of the other bulbs
would remain lit.
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CRCT Preparation
Chapter 17
2. Tara rubs a balloon on her hair and charges
both the balloon and her hair. What will happen
if Tara holds the balloon close to her
hair? A Her hair will be repelled by the balloon
because her hair and the balloon have the same
charge. B Her hair will be attracted to the
balloon because her hair and the balloon have the
same charge. C Her hair will be repelled by the
balloon because her hair and the balloon are
oppositely charged. D Her hair will be attracted
to the balloon because her hair and the balloon
are oppositely charged.
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CRCT Preparation
Chapter 17
2. Tara rubs a balloon on her hair and charges
both the balloon and her hair. What will happen
if Tara holds the balloon close to her
hair? A Her hair will be repelled by the balloon
because her hair and the balloon have the same
charge. B Her hair will be attracted to the
balloon because her hair and the balloon have the
same charge. C Her hair will be repelled by the
balloon because her hair and the balloon are
oppositely charged. D Her hair will be attracted
to the balloon because her hair and the balloon
are oppositely charged.
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CRCT Preparation
Chapter 17
3. How does the electric force act within an
atom? A The electric force causes the repulsion
of the negatively-charged electrons from the
positively-charged nucleus. B The electric force
causes the attraction of negatively-charged
electrons to the positively charged
nucleus. C The electric force holds neutrons and
protons together in the nucleus. D The electric
force causes the attraction of negatively-charged
electrons to each other.
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Chapter 17
3. How does the electric force act within an
atom? A The electric force causes the repulsion
of the negatively-charged electrons from the
positively-charged nucleus. B The electric force
causes the attraction of negatively-charged
electrons to the positively charged
nucleus. C The electric force holds neutrons and
protons together in the nucleus. D The electric
force causes the attraction of negatively-charged
electrons to each other.
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CRCT Preparation
Chapter 17
4. When Andre plugs his stereo into the same
outlet as the television and lamp, all three
wont work. What is the most likely hypothesis
for what happened? A The circuit was overloaded,
and the circuit breaker opened. B The circuit was
complete, and the circuit breaker closed. C Only
the stereo operates on alternating current. D The
stereos electrical cord was faulty.
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CRCT Preparation
Chapter 17
4. When Andre plugs his stereo into the same
outlet as the television and lamp, all three
wont work. What is the most likely hypothesis
for what happened? A The circuit was overloaded,
and the circuit breaker opened. B The circuit was
complete, and the circuit breaker closed. C Only
the stereo operates on alternating current. D The
stereos electrical cord was faulty.
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CRCT Preparation
Chapter 17
5. Which of the following electrical devices
could be used to monitor the temperature of an
engine? A a thermocouple B a photocell C a dry
cell D a battery
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CRCT Preparation
Chapter 17
5. Which of the following electrical devices
could be used to monitor the temperature of an
engine? A a thermocouple B a photocell C a dry
cell D a battery
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CRCT Preparation
Chapter 17
6. A scientist measured the distance between two
positively-charged objects and determined the
electric force between them. Based on the data in
the table, which of the following statements is
true?
A As the distance between the objects increases,
the size of the electric force decreases. B As
the distance between the objects increases, the
objects become more positively charged.
C The size of the electric force is constant. D
As the size of the objects increases, the size of
the electric force between them decreases.
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CRCT Preparation
Chapter 17
6. A scientist measured the distance between two
positively-charged objects and determined the
electric force between them. Based on the data in
the table, which of the following statements is
true?
A As the distance between the objects increases,
the size of the electric force decreases. B As
the distance between the objects increases, the
objects become more positively charged.
C The size of the electric force is constant. D
As the size of the objects increases, the size of
the electric force between them decreases.
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CRCT Preparation
Chapter 17
7. Suki can have all five appliances in her
kitchen on at the same time, or she can have each
appliance on one at a time. How are the
appliances in Sukis kitchen wired? A in a single
loop B in a direct current circuit C in a
parallel circuit D in a series circuit
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CRCT Preparation
Chapter 17
7. Suki can have all five appliances in her
kitchen on at the same time, or she can have each
appliance on one at a time. How are the
appliances in Sukis kitchen wired? A in a single
loop B in a direct current circuit C in a
parallel circuit D in a series circuit
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CRCT Preparation
Chapter 17
8. How should Pedro wire four bulbs in a circuit
so that all the bulbs shine as brightly as
possible? A He should wire all four bulbs in a
series circuit. B He should wire two bulbs in a
parallel circuit and the other two bulbs in a
series circuit. C He should wire three bulbs in a
series circuit and the other bulb in a parallel
circuit. D He should wire all four bulbs in a
parallel circuit.
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CRCT Preparation
Chapter 17
8. How should Pedro wire four bulbs in a circuit
so that all the bulbs shine as brightly as
possible? A He should wire all four bulbs in a
series circuit. B He should wire two bulbs in a
parallel circuit and the other two bulbs in a
series circuit. C He should wire three bulbs in a
series circuit and the other bulb in a parallel
circuit. D He should wire all four bulbs in a
parallel circuit.
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CRCT Preparation
Chapter 17
9. Which of the following copper wires will have
the least amount of resistance? A a short, thin
wire B a short, thick wire C a long, thin
wire D a long, thick wire
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CRCT Preparation
Chapter 17
9. Which of the following copper wires will have
the least amount of resistance? A a short, thin
wire B a short, thick wire C a long, thin
wire D a long, thick wire
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CRCT Preparation
Chapter 17
10. Two kinds of electric current exist direct
current and alternating current. Explain the
difference between these two kinds of current and
give an example of where you might find each kind
of current.
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CRCT Preparation
Chapter 17
10. Answer In direct current, the charges
always flow in the same direction. In alternating
current, the charges continually shift from
flowing in one direction to flowing in the
reverse direction. Students should give at least
one example of direct current being used. Any
battery-operated device, such as a flashlight or
an MP3 player, is an acceptable example. Students
should give at least one example of alternating
current being used. Any electrical device that is
plugged into an outlet, such as a lamp or a fan,
is an acceptable example.
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CRCT Preparation
Chapter 17
11. On a rainy day, David wears rubber boots to
school. The floors in his math classroom are
covered with carpet. After David walks across the
room to the pencil sharpener, he gets a shock
when he touches the sharpener. Explain why David
got a shock.
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CRCT Preparation
Chapter 17
11. Answer When David walked across the room,
his rubber boots rubbed the carpet and electrons
from the carpet were transferred to David.
Negative charges built up in David as static
electricity. The static electricity discharged
rapidly when David touched the sharpener. The
discharge gave David a shock.