Sand is being dropped on a conveyer belt at the rate of 2 kg per second. The force necessary to keep the belt moving with a constant speed of 3 ms-1 will be

Question

Sand is being dropped on a conveyer belt at the rate of 2 kg per second. The force necessary to keep the belt moving with a constant speed of 3 ms-1 will be (A) 12 N (B) 6 N (C) zero (D) 18 N

Tardigrade Admin · Accepted Answer

Here, rate of fall of sand on conveyer belt, (dm/dt)=2 kg s-1 Conveyer belt speed v = 3 ms-1 Force F = ? F=v (dm/dt)=3×2=6N

Q. Sand is being dropped on a conveyer belt at the rate of 2 kg per second. The force necessary to keep the belt moving with a constant speed of $3 m s^{- 1}$ will be

$12 N$

$6 N$

zero

$18 N$

Here, rate of fall of sand on conveyer belt,
$\frac{d m}{d t} = 2 k g s^{- 1}$
Conveyer belt speed $v = 3 m s^{- 1}$ Force $F = ?$
$F = v \frac{d m}{d t} = 3 \times 2 = 6 N$

Q. Sand is being dropped on a conveyer belt at the rate of 2 kg per second. The force necessary to keep the belt moving with a constant speed of 3ms−1 will be

12N

6N