MCQ
A source of sound is travelling with a velocity $40\, km/hour$ towards observer and emits sound of frequency $2000 Hz$. If velocity of sound is $1220 \,km/hour$, then what is the apparent frequency heard by an observer  .... $Hz$
  • A
    $2210$
  • B
    $1920$
  • $2068 $
  • D
    $2086$

Answer

Correct option: C.
$2068 $
c
(c) $n' = n\,\left( {\frac{v}{{v - {v_S}}}} \right) = \frac{{2000 \times 1220}}{{(1220 - 40)}} = 2068\,Hz$

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