Q16 of 28 Page 159

A man carrying a bag of total mass 25kg climbs up to a height of 10m in 50 seconds. Calculate the power delivered by him on the bag.

Given data,

mass(m)=25 kg


displacement(s) = 10 m


time taken(t) = 50 s


As the man is working against gravity so force(F) applied is


mg= 25 kg × 10 m/s2 = 250 N


Power = work done/time taken


=(force×displacement)/(time taken)


=


=50 watt(w)


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