Question

Gravels are dropped on a conveyor belt at the rate of 0.5 kg/sec. The extra force required in newtons to keep the belt moving at 2 m/sec is

• A. 1
• B. 2
• C. 4
• D. 0.5

Answer 1

Answer: (A)

1

Answer 2

Opposing force

$F = u\mspace{6mu}\left( \frac{dm}{dt} \right) = 2 \times 0.5 = 1\mspace{6mu} N$ $\left( \text{As,}\mspace{6mu} F = u\frac{du}{dt} \right)$

So same amount of force is required to keep the belt moving at 2 m/s