Multiple Choice Identify the
choice that best completes the statement or answers the question.
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1.
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A _____ transformer is used near homes to achieve a voltage of 120 V.
a. | step-up | c. | primary-coil | b. | step-down | d. | secondary-coil |
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2.
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A transverse wave containing perpendicular electrical and magnetic fields is
called a(n)
a. | electromagnetic wave. | c. | AC wave. | b. | electric wave. | d. | solar wave. |
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3.
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The north pole of one magnet will be
a. | attracted to the north pole of another magnet. | b. | repelled by the
center of another magnet. | c. | repelled by the north pole of another
magnet. | d. | repelled by the south pole of another magnet. |
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4.
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The magnetism of a piece of magnetized iron can be weakened by
a. | heating the iron and hammering it. | b. | putting it near a piece of unmagnetized
iron. | c. | bending the iron. | d. | None of the
above |
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5.
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Which of the compass needle orientations in
the figure above might correctly describe the magnet’s field at that point?
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6.
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What instrument is used to trace the direction of a magnetic field?
a. | lodestone | c. | compass | b. | limestone | d. | transformer |
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7.
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What material was used to make the first compass?
a. | lodestone | c. | iron | b. | limestone | d. | steel |
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8.
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Magnetic fields are produced by
a. | electric charges. | c. | gravitational force. | b. | electric currents. | d. | water currents. |
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9.
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Groups of atoms that align to form small, magnetized regions in a material are
a. | geographic domains. | c. | magnetic domains. | b. | magnetic field lines. | d. | magnetic poles. |
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10.
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A device that converts electrical energy into mechanical energy is a(n)
a. | generator. | c. | commutator. | b. | electric motor. | d. | transformer. |
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11.
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In an AC generator, the magnitude of the current produced
a. | depends on the orientation of the loop in a magnetic field. | b. | is zero when the
loop is perpendicular to the magnetic field. | c. | varies with time. | d. | All of the
above |
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12.
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Light travels as
a. | electrical waves. | c. | electromagnetic waves. | b. | magnetic
waves. | d. | electrochemical
waves. |
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13.
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A transformer changes
a. | both the amperage and the voltage of AC current. | b. | the voltage of AC
current. | c. | the amperage of AC current. | d. | the resistance of AC
current. |
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14.
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Like magnetic poles always
a. | repel each other. | c. | point toward the south pole. | b. | attract each
other. | d. | point toward the
north pole. |
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15.
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An example of a naturally occurring magnetic rock is
a. | lodestone. | c. | limestone. | b. | soapstone. | d. | peastone. |
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16.
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The strength of the magnetic field of a magnet
a. | decreases as distance from the magnet decreases. | b. | decreases as
distance from the magnet increases. | c. | increases as distance from the magnet
increases. | d. | remains the same at any distance from a magnet. |
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17.
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A compass needle naturally points toward
a. | the geographic North Pole. | c. | Earth’s magnetic north
pole. | b. | the S pole of a magnet. | d. | All of the above |
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18.
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Earth’s magnetic poles are located in
a. | Canada and Australia | b. | Canada and Alaska. | c. | Canada and
Antarctica. | d. | the same places as the geographic poles. |
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19.
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A magnetic field around a current-carrying wire forms
a. | lines tangent to the wire. | c. | lines parallel to the
wire. | b. | lines perpendicular to the wire. | d. | concentric circles around the
wire. |
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20.
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The strength of the magnetic field of a solenoid can be increased by
a. | decreasing the number of loops on the solenoid. | b. | decreasing the
current in the solenoid. | c. | increasing the number of loops on the
solenoid. | d. | increasing the resistance of the solenoid. |
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21.
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When a magnetic field is applied near iron, the iron’s domains
a. | scatter and decrease the iron’s magnetic field. | b. | align and increase
the iron’s magnetic field. | c. | scatter and increase the iron’s magnetic
field. | d. | align and decrease the iron’s magnetic field. |
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22.
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When the loop of wire in an AC generator rotates halfway,
a. | the current reverses direction. | b. | the current continues in the same
direction. | c. | electrical energy is converted into mechanical energy. | d. | maximum current is
reached. |
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23.
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Both electric and magnetic fields in an electromagnetic wave are
a. | perpendicular to the direction that the wave travels. | b. | parallel to the
direction that the wave travels. | c. | opposite the direction that the wave
travels. | d. | tangential to the direction that the wave travels. |
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24.
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Transformers can
a. | increase voltage. | c. | decrease voltage. | b. | neither increase nor decrease
voltage. | d. | increase nor
decrease voltage. |
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Matching
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Match each item with the correct statement below. a. | electromagnetic induction | d. | generator | b. | transformer | e. | step-down | c. | step-up | f. | alternating
current |
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25.
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a machine that converts mechanical energy into electrical energy
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26.
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a transformer with fewer loops on the secondary coil than the primary
coil
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27.
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the process of creating a current in a circuit by changing a magnetic
field
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28.
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an electric current that changes direction at regular intervals
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29.
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a device that increases or decreases AC current voltage
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30.
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a transformer with more loops on the secondary coil than the primary
coil
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