Question 88: Work, Energy and Power & Circular Motion

Question

Sand is being dropped from a stationary dropper at a rate of $$0.5 \,\mathrm{kgs}^{-1}$$ on a conveyor belt moving with a velocity of $$5 \mathrm{~ms}^{-1}$$. The power needed to keep the belt moving with the same velocity will be :

Accepted Answer

$${{dm} \over {dt}} = 0.5$$ kg/s
$$v = 5$$ m/s
$$F = {{vdm} \over {dt}} = 2.5$$ kg m/s
2
$$P = \overline F \,.\,\overline v  = (2.5)(5)$$ W
$$ = 12.5$$ W

Answer

1.25 W

Answer

2.5 W

Answer

6.25 W

Answer

12.5 W

Work, Energy and Power & Circular Motion

Sand is being dropped from a stationary dropper at a rate of $0.5 \,\mathrm{kgs}^{-1} on a conveyor belt moving with a velocity of 5 \mathrm{~ms}^{-1}$. The power needed to keep the belt moving with the same velocity will be :

Choose the correct answer: