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Question
Two sound waves move in the same direction in the same medium. The pressure amplitudes of the waves are equal but the wavelength of the first wave is double the second. Let the average power transmitted across a cross section by the first wave be P1 and that by the second wave be P2. Then
Options
\[P_1 = P_2\]
\[P_1 = 4 P_2\]
\[P_2 = 2 P_1\]
\[P_2 = 4P .\]
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Solution
\[P_1 = P_2\]
Since the average power transmitted by a wave is independent of the wavelength, we have \[P_1 = P_2\]
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