A girl of mass $40\ kg$ climbs a rope $6\ m$ long at constant speed in $15\ seconds$. What power she expands during the climb?

Academic Physics NCERT Class 9

Here given, mass of the girl $m=40\ kg.$

Height climbed by the girl $h=6\ m$

Time taken to climb $t=15\ sec.$

Work done by the girl to climb the rope $W=mgh$

$=40\times9.8\times 6$

$=2,352\ Joule$

Therefore, Power used to climb the rope $P=\frac{W}{t}$

$=\frac{2352}{15}$

$=156.8\ Watt$

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Updated on: 10-Oct-2022

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