NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

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Application +4 | -1

A steel ball of mass

2 {~g}

is thrown downward with velocity

20 {~ms}^{-1}

from height

9.4 {~m}

. It penetrates into the sand by

60 {~cm}

and then it stops. The change in mechanical energy of steel ball will be

\left[g=10 {~ms}^{-2}\right]

View answer and explanation

Correct option: B

-0.6 {~J}

Option B (-0.6 J) is correct because the change in mechanical energy is the difference between the initial mechanical energy and the final mechanical energy, which is negative due to energy loss from penetration into the sand.

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