How is the power related to the speed at which a body can be lifted ? How many kilograms will a man working at the power of 100 W, be able to lift at constant speed of `1 m//s` vertically ? (g= 10 m//s^2)`

Explanation

(i) The power delivered to a body can also expressed in term of the force F applied to the body and the velocity v of the body
`"Power"(P)=("work")/("time")rArrP=(F.s)/(t)`
where F = Force, S = displacement and t = time
`P=F.v" "[:'W=F.s]`
`(":'v=(s)/(t))[v=""velocity of body"]`
Given, power `(P)=100W,v=1ms^(-2)and =10ms^(-2)`
We know that, power (P)=F.v
`rArrp=mg.v" "[:'F=mg]`
100=mg.v
`100=mxx10xx1rArrm=(100)/(10)`
`rArr m=10kg`
Therefore, man working at the power of 100 W can lift 10 kg.