A 10 m long iron chain of linear mass density $0.8{\rm{\;kg\;}}{{\rm{m}}^{ - 1}}$ is hanging freely from a rigid support. If ${\rm{g}} = 10{\rm{\;m}}{{\rm{s}}^{ - 2}}$, then the power required to lift the chain upto the point of support in 10 s is

JEE PHYSICS MCQ: WORK-ENERGY-POWER

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A 10 m long iron chain of linear mass density

0.8\mathrm{\;kg\;}{\mathrm{m}^{ - 1}}

is hanging freely from a rigid support. If

\mathrm{g} = 10\mathrm{\;m}{\mathrm{s}^{ - 2}}

, then the power required to lift the chain upto the point of support in 10 s is

View answer and explanation

Correct option: D

40 W

The correct answer is D (40 W) because the power required is calculated by finding the potential energy gained by lifting the chain and dividing by the time taken.

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