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14. waves and sound — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysics14. waves and sound1 Mark
MCQ
An observer is approaching with a speed $v$, towards a stationary source emitting sound waves of wavelength $\lambda_0$. The wavelength shift detected by the observer is (Take $c=$ speed of sound)
  • A
    $\frac{\lambda_0 V}{c}$
  • B
    $\frac{\lambda_0 c}{v}$
  • C
    $\frac{\lambda_0 v^2}{c^2}$
  • ✓
    Zero
✓

Answer

Correct option: D.
Zero
d
(d)

In Doppler effect only change in frequency is observed and not change in wavelength if observer approaches the source.

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