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Question
When we clap our hands, the sound produced is best described by Here p denotes the change in pressure from the equilibrium value.
Options
\[p = p_0 \sin\left( kx - \omega t \right)\]
\[p = p_0 \sin kx \cos \omega t\]
\[p = p_0 \cos kx \sin \omega t\]
\[p = \sum p_{0n} \sin \left( k_n x - \omega_n t \right)\]
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Solution
\[p = \sum p_{0n} \sin \left( k_n x - \omega_n t \right)\]
When we clap, there is a change in pressure, which sets a disturbance and forms a wave. However, this variation is not uniform every time we clap (unlike in the case of a sound wave). Hence, we sum up all the disturbances.
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