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–1 vertically? (g = 10 m s–2)
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Power = work/time work=force x displacement force = mass x acceleration acceleration=velocity/time
Therefore
Power= velocity×mass× displacement
time × time
Here Power,P=100W velocity,v=1m/s since time,t=1s displacement, s=1m acceleration,a=10m/s
From equation P=m×a×s
t 100=m×10
m=10
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