Work Energy And Power Question 292
Question: An electric pump is used to fill an overhead tank of capacity $ 9m^{3} $ kept at a height of 10m above the ground. If the pump takes 5 minutes to fill the tank by consuming 10 kW power the efficiency of the pump should be $ ( g = 10 m{s^{-2}} ) $
Options:
A) 60%
B) 40%
C) 20%
D) 30%
Show Answer
Answer:
Correct Answer: D
Solution:
[d] $ P _{out}=\frac{mgh}{t}=\frac{9000\times 10\times 10}{5\times 60}=3600W $
$ P _{in}=10\times 10^{3}w. $
$ \therefore \eta =\frac{P _{out}}{P _{in}}\times 100=\frac{3000}{10\times 10^{3}}\times 100=30% $
