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15 Cards in this Set
- Front
- Back
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What is wave propagation
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Invisable force that enables man to comminicate over long distances
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What is a transverse wave?
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Type of wave motion ei- radio, light and heat
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What is a longitudinal wave?
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Sound wave
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What is refraction?
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When a wave traveling through two different mediums passes through the boundry of the mediums and bends towards or away from the Normal.
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What is reverberation?
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The multiple reflections of sound waves
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What is resonance
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It occurs when objects vibrates at its natural freq.
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What antenna transmits an electomagnetic wave perpendiculat to the Earth's surface?
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Vertically polarized
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What antenna transmits an electomagnetic wave parallel to the Earth's surface?
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Horizontally polarized
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That layer of the atmosphere does virtually all weather take place?
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Troposhpere
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What layer of the atmosphere has a little effect on radio waves?
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Stratoshere
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What layer of the atmosphere has electrically charged ions which aid in long distance comms?
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Ionosphere
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What is the difference between surface waves and space waves?
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Surface waves travle along the contour of the earth and space waves travel through the air or can be feflected from the surface of the earth.
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What layer of the earth is responsible for low freqs?
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D
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What layer of the earth is responsible for high freq and long range transmission?
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F
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Define reciprocity
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The various properties fo the antenna apply equally to transmitting and receiving.
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