Physics - Sound Wave Question with Solution | TestHub

PhysicsSound WaveDopler's effectHard2 minPYQ_2020

PhysicsHardsingle choice

When a train approaches a stationary observer, the apparent frequency of the whistle is $n^{'}$ and when the same train recedes away from the observer, the apparent frequency is $n^{''}$ . The apparent frequency $n$ , when the observer moves with the train is

Options:

Answer:

Solution:

$n^{'} = \frac{v n}{v - v_{s}}, n^{''} = \frac{v n}{v + v_{s}}$

$∴ \frac{n}{n^{'}} = 1 - \frac{v_{s}}{v}, \frac{n}{n^{''}} = 1 + \frac{v_{s}}{v}$

Adding the two, we get

$\frac{n}{n^{'}} + \frac{n}{n^{''}} = 2 ∴ n = \frac{2 n^{'} n^{''}}{n^{'} + n^{''}}$

Stream:JEESubject:PhysicsTopic:Sound WaveSubtopic:Dopler's effect

⏱ 2mℹ️ Source: PYQ_2020

Doubts & Discussion

Loading discussions...