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NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

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Application +4 | -1

A mason is supplied with bricks by his assistant who is

3 {~m}

below him, the assistant is tossing the brick vertically up. The speed of the brick, when it reaches the mason is

2 {~ms}^{-1}

. What percentage of energy used up by the servant serves no useful purpose?

View answer and explanation

Correct option: A

5.6

Option C is incorrect. The correct answer is 5.8. The percentage of energy used up by the servant serves no useful purpose is calculated by finding the initial velocity and then calculating the percentage of potential energy converted to kinetic energy.

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{A}

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