Question:
A source has wavelength 60 cm when it is stationary. If the speed of sound in air is 320m s⁻¹ and the source moves with speed 20m s⁻¹, the wavelength in the forward direction will be
A source has wavelength 60 cm when it is stationary. If the speed of sound in air is 320m s⁻¹ and the source moves with speed 20m s⁻¹, the wavelength in the forward direction will be
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Forward wavelength decreases when source moves towards observer.
Updated On: Mar 18, 2026
- 56 cm
- 60 cm
- 64 cm
- 68 cm
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The Correct Option is A
Solution and Explanation
Step 1: λ'=λ((v-uₛ)/(v))
Step 2: λ'=60×(320-20)/(320)=56 cm
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