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A boy of mass 40 kg runs up a flight of ...

A boy of mass 40 kg runs up a flight of 50 steps,each of 10 cm high, in 5s, Find the power developed by the boy,

A

`200W`

B

`300W`

C

`400W`

D

`500W`

Text Solution

Verified by Experts

The correct Answer is:
C
Here,mass of the boy, `m =40 kg`
total height gained, `h =50xx10cm 500cm =5m`
time taken to climb, t =5 s
Work done by the boy, `W = mgh =(40kg)(10m//s^2)(5m) =2000J`
power developed `P = (W)/(t) =(2000J)/(5s) = 400W`
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