Q. 164.8( 8 Votes )

# A boy of mass 50 kg runs up a staircase of 45 steps in 9s. If the height of each step is 15 cm, find his power. (Take g = 10 ms^{-2})

Answer :

Given

Mass of Body (m) = 50 Kg,

Time (t) = 9s,

Height of each step = 15 cm,

Acceleration due to gravity (g) = 10 m/s^{2}.

Now

Weight = mg = 50×10 = 500N

Height of staircase =

(∵ 1 m = 100 cm)

Power =

⇒ Power =

Power = 375 Watt

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