Question

A train is moving with velocity 20 m/sec. on this, dust is falling at the rate of 50 kg/min. The extra force required to move this train with constant velocity will be

• A. 16.66 N
• B. 1000 N
• C. 166.6 N
• D. 1200 N

Answer 1

Answer: (A)

16.66 N

Answer 2

Force $F = v\frac{dm}{dt}$ $= 20 \times \frac{50}{60} = 16.66N$