NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

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An iron nail is dropped from a height h from the level of a sand bed. If it penetrates through a distance x in the sand before coming to rest, then average force exerted by the sand on nail is

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Correct option: A

m\mathrm{g}\left( {\frac{h}{x} + 1} \right)

Option A (

m\mathrm{g}\left( {\frac{h}{x} + 1} \right)

) is correct because it is derived from the work-energy theorem, considering both the gravitational potential energy and the work done by the sand.

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{A}

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2\mathrm{\;m}{\mathrm{s}^{ - 1}}

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is A force

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