Suppose that the speed of sound in air at a given temperature is … - Vidyadip

MCQ

Suppose that the speed of sound in air at a given temperature is $400 m/sec$. An engine blows a whistle at $1200 Hz$ frequency. It is approaching an observer at the speed of $100 m/sec$. What is the apparent frequency as heard by the observer .... $Hz$

A
$600$
B
$1200$
C
$1500$
✓
$1600$

✓

Answer

Correct option: D.

$1600$

d
(d) $ n' = n\,\left( {\frac{v}{{v - {v_S}}}} \right) = 1200\,\left( {\frac{{400}}{{400 - 100}}} \right) = 1600\,Hz$

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