If you apply $1\ J$ of energy to lift a book of $0.5\ kg$, how high will it rise? [Take $g=10\ ms^{-2}$]

Academic Physics NCERT Class 9

Energy used to lift the book $P=1\ J$

Mass of the book $m=0.5\ kg.$

$g=10\ ms^{-2}$

Let the height $h=?$

Energy used $P=mgh$

Therefore, $0.5\times10\times h=1$

Or $5h=1$

Or $h=\frac{1}{5}\ m=0.2\ m$

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Updated on: 10-Oct-2022

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