The wavelength is $120 cm$ when the source is stationary. If the source is moving with relative velocity of $60\, m/sec$ towards the observer, then the wavelength of the sound wave reaching to the observer will be ... $cm$ (velocity of sound $= 330 \,m/s$)
  • A$98$
  • B$140$
  • C$120$
  • D$ 144$
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