Question

An open carriage in a goods train is moving with a uniform velocity of $10m{s}^{-1}$. If the rain adds water with zero velocity at the rate of $5kg{s}^{-1}$, then the additional force applied by the engine to maintain the same velocity of the train is

• A. 0.5 N
• B. 2.0 N
• C. 50 N
• D. 25 N

Answer 1

Answer: (C)

$F=v\frac{dm}{dt}=10\times 5N=50N$