A source of sound is moving towards a stationary observer with $\left(\frac{1}{10}\right)^{\text {th }}$ the…
A source of sound is moving towards a stationary observer with $\left(\frac{1}{10}\right)^{\text {th }}$ the of the speed of sound. The ratio of apparent to real frequency is
$10:9$
$11:10$
$(11)^2:(10)^2$
$(9)^2:(10)^2$
Solution
For source of sound moving towards a stationary observer, the apparent frequency is given by, $\mathrm{n}=\mathrm{n}_0 \times \frac{\mathrm{v}}{\mathrm{v}-\mathrm{v}_{\mathrm{S}}}$
$\begin{aligned}
& \therefore \quad \frac{\mathrm{n}}{\mathrm{n}_0}=\frac{\mathrm{v}}{\mathrm{v}-\frac{\mathrm{v}}{10}} \\
& \therefore \quad \frac{\mathrm{n}}{\mathrm{n}_0}=\frac{10}{9}
\end{aligned}$