Question

A person is moving a block of mass = 1 kg with constant speed v = 1 m/s .Block is placed on a rough horizontal surface. The coefficient of friction between block and surface is $\mu$ = 0.5 then find out the power delivered by a man.

Answer 1

Given,

Coefficient of friction,$\mu =0.5$

Mass, $m=1kg$

Friction force, $F=\mu mg=0.5\times 1\times 10=5N$

Velocity, $v=1m{s}^{-1}$

Average power delivered, $P=F.v=5\times 1=5W$

Hence, power delivered by man is $5W$