Question 28

The speed of sound in air is roughly $340ms^{-1}$ so P cannot be true.

5mm is too big for a mean to peak disturbance; it is a peak to peak disturbance.

$c=f\lambda$ yields a wavelength of $68mm$.

The question gives the time period as $0.20ms$ so the frequency is $\frac{1}{0.2\times10^{-3}}=5000Hz$.

Therefore S is the only true statement.

The speed of sound in air is roughly $340ms^{-1}$ so P cannot be true.

5mm is too big for a mean to peak disturbance; it is a peak to peak disturbance.

$c=f\lambda$ yields a wavelength of $68mm$.

The question gives the time period as $0.20ms$ so the frequency is $\frac{1}{0.2\times10^{-3}}=5000Hz$.

Therefore S is the only true statement.