True/False
Indicate whether the sentence or statement is true
or false.
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1.
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Beyond some distance from the source, we can approximate a wavefront by assuming it is
flat.
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2.
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Radio
waves can be reflected, but not diffracted.
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3.
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Because of diffraction, radio waves can sometimes "bend" around a
corner.
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Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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4.
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Radio
waves were first demonstrated experimentally by: a. | Armstrong | c. | Maxwell | b. | Hertz | d. | Marconi | | | | |
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5.
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Which
of the following are electromagnetic: a. | radio waves | c. | gamma waves | b. | light | d. | all of the
above | | | | |
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6.
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Which
is a possible polarization for an electromagnetic wave: a. | vertical | c. | circular | b. | horizontal | d. | all of the above | | | | |
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7.
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The
"attenuation of free space" is due to: a. | losses in the characteristic impedance of free
space | b. | losses due to absorption in the upper
atmosphere | c. | the decrease in energy per square meter due to expansion of the
wavefront | d. | the decrease in energy per square meter due to absorption of
the wavefront | | |
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8.
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Space
waves are: a. | line-of-sight | b. | reflected off the ionosphere | c. | same as sky
waves | d. | radio waves used for satellite
communications | | |
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9.
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"Ghosts" on a TV screen are an example of: a. | fading | c. | multipath
distortion | b. | diffraction | d. | cancellation due to reflection | | | | |
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10.
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As a
cell-phone user passes from one cell to another: a. | a "handoff" process
occurs | c. | both cells will
handle the call | b. | a "sectoring" process
occurs | d. | nothing
occurs | | | | |
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