MCQ
A man sets his watch by the sound of a siren placed at a distance $1 \,km$ away. If the velocity of sound is $330 \,m/s$
- AHis watch is set $3 sec$. faster
- ✓His watch is set $3 sec$. slower
- CHis watch is set correctly
- DNone of the above
✓
Answer
Correct option: B.
His watch is set $3 sec$. slower
b
(b) ${\rm{Time}} = \frac{{{\rm{Distance }}}}{{{\rm{Velocity}}}} = \frac{{1000}}{{330}} = 3.03\,\sec $.
Sound will be heard after $3.03 \,sec.$ So his watch is set $3sec$, slower.
(b) ${\rm{Time}} = \frac{{{\rm{Distance }}}}{{{\rm{Velocity}}}} = \frac{{1000}}{{330}} = 3.03\,\sec $.
Sound will be heard after $3.03 \,sec.$ So his watch is set $3sec$, slower.
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