MHT CET · Physics · Waves and Sound
With what velocity an observer should move relative to a stationary source so that
a sound of double the frequency of source is heard by an observer?
- A Half the velocity of sound towards the source.
- B Same as velocity of sound away from the source.
- C Twice the velocity of sound towards the source.
- D Same as velocity of sound towards the source.
Answer & Solution
Correct Answer
(D) Same as velocity of sound towards the source.
Step-by-step Solution
Detailed explanation
Correct option is A)
By using \(n^{\prime}=n\left(\frac{v}{v-v_{s}}\right)\)
\(2 \mathrm{n}=\mathrm{n}\left(\frac{\mathrm{v}-\mathrm{v}_{0}}{\mathrm{v}-0}\right)\)
\(\Rightarrow \mathrm{v}_{0}=-\mathrm{v}=-(\) Speed of sound \()\)
Negative sign indicates that observer is moving opposite to the direction of velocity of sound, as shown
By using \(n^{\prime}=n\left(\frac{v}{v-v_{s}}\right)\)
\(2 \mathrm{n}=\mathrm{n}\left(\frac{\mathrm{v}-\mathrm{v}_{0}}{\mathrm{v}-0}\right)\)
\(\Rightarrow \mathrm{v}_{0}=-\mathrm{v}=-(\) Speed of sound \()\)
Negative sign indicates that observer is moving opposite to the direction of velocity of sound, as shown
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