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

Gujarat BoardEnglish MediumSTD 11 SciencePhysics14. waves and sound1 Mark
MCQ
A source emits a sound of frequency of $400 Hz$, but the listener hears it to be $390 Hz.$ Then
  • A
    The listener is moving towards the source
  • B
    The source is moving towards the listener
  • ✓
    The listener is moving away from the source
  • D
    The listener has a defective ear
✓

Answer

Correct option: C.
The listener is moving away from the source
c
(c)Since apparent frequency is lesser than the actual frequency, hence the relative separation between source and listener should be increasing.

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