MCQ
A train is moving with velocity $20\, m/sec$. on this dust is falling at the rate of $50 \,kg/minute$. The extra force required to move this train with constant velocity will be ....... $N$
- ✓$16.66$
- B$1000$
- C$166.6$
- D$1200$
✓
Answer
Correct option: A.
$16.66$
a
(a)$F = u\;\left( {\frac{{dm}}{{dt}}} \right) = 20 \times \frac{{50}}{{60}} = 16.66\,N$
(a)$F = u\;\left( {\frac{{dm}}{{dt}}} \right) = 20 \times \frac{{50}}{{60}} = 16.66\,N$
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