MCQ
A siren emitting sound of frequency $500 \;Hz$ is going away from a static listener with a speed of $50\, m/sec$. The frequency of sound to be heard, directly from the siren, is .... $Hz$
- ✓$434.2$
- B$589.3$
- C$481.2$
- D$286.5$
✓
Answer
Correct option: A.
$434.2$
a
(a) $n' = n\,\left( {\frac{v}{{v + {v_S}}}} \right) = 500 \times \left( {\frac{{330}}{{300 + 50}}} \right) = 434.2Hz$
(a) $n' = n\,\left( {\frac{v}{{v + {v_S}}}} \right) = 500 \times \left( {\frac{{330}}{{300 + 50}}} \right) = 434.2Hz$
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