Q. A coolie 1.5 m tall raises a load of 80 kg in 2 s from the ground to his head and then walks a distance of 40 m in another 2 s. The power developed by the coolie is $\lbrack g = 10\ ms^{- 2}\rbrack$
A) 0.2 kW
B) 0.4 kW
C) 0.6 kW
D) 0.8 kW
Explanation
(c) $P = \frac{mgh}{t} = \frac{80 \times 10 \times 1.5}{2}$
$= 600\ W\ = \ 0.6\ kW$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.