UNIVERSE
PLANETARY INTERIORS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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P waves
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S waves
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Either A or B
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None of the above
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Detailed explanation-1: -P waves travel fastest and are the first to arrive from the earthquake. In S or shear waves, rock oscillates perpendicular to the direction of wave propagation. In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.
Detailed explanation-2: -In air, P waves take the form of sound waves and therefore move at the speed of sound, 330m/s at sea level. Some people even report hearing an earthquake (due to the higher frequency P waves vibrating or rustling objects) before they feel the S waves’ arrival.
Detailed explanation-3: -The primary, or P, waves travel most quickly and are the first to be registered by the seismograph. Secondary, or S, waves travel more slowly. As S waves have a greater amplitude than P waves the two groups are easily distinguishable on the seismogram.