A sound wave is propagating through a medium such that displacement v/s x graph is as shown. The corresponding excess pressure v/s x graph will be:

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TestHub · Accepted Answer

The excess pressure is the negative bulk-modulus times the slope of the displacement graph:
$p = - B \frac{d y}{d x}$
The printed displacement graph is triangular, so $\frac{d y}{d x}$ is a positive constant on the rising part and an equal negative constant on the falling part.
Hence $p$ is a negative constant over the first half and a positive constant over the second half - a square wave starting below the axis.
This matches graph (D).

Physics - Sound Wave Question with Solution | TestHub

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