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Question
Given below are some functions of x and t to represent the displacement (transverse or longitudinal) of an elastic wave. State which of these represent (i) a traveling wave, (ii) a stationary wave or (iii) none at all:
y = 3 sin (5x – 0.5t) + 4 cos (5x – 0.5t)
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Solution
The given equation represents a travelling wave as the harmonic terms kx and ωtare in the combination of kx – ωt.
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