Physics
A boy weighing 350 N climbs up 30 steps, each 20 cm high in 1 minute.
Calculate:
(i) the work done, and
(ii) the power spent.
Work, Energy & Power
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Answer
We know,
work done = Force × distance moved in direction of force
i.e. W = F × S
Given,
Force = 350 N
Distance covered in 30 steps (S)
S = 30 x 20 cm = 600cm
⇒ S = 6m
Substituting the values of F and S
∴ Work done by boy = 2100J
(ii)
∴ Power spent by boy = 35W
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