NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

1 Easy

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Application +4 | -1

Sand is falling on a conveyor belt at the rate of

5\,kg\,{s^{ - 1}}

. The extra power required to move the belt with a velocity of

6\,m{s^{ - 1}}

View answer and explanation

Correct option: B

180 W

The correct answer is B. The extra power required is equal to the rate of change of kinetic energy of the sand. P = d/dt (1/2 * m * v²) = v² * dm/dt = (6 m/s)² * 5 kg/s = 180 W.

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