An engine pumps water through a hose pipe. Water passes through the pipe and leaves it with a velocity of `2 ms^(1)`. The mass per unit length of water in the pipe is `100 kgm^(-1)`. What is the power of the engine?

Options

A. `400W`
B. `200 W`
C. `100 W`
D. `800W`

Answer

A

Explanation

Mass `//` length `=100kg//m`
velocity `=(l en g th)/(time)=2m//s` `:.` mass `//` time ,`m=100xx2=200kg//s.`
Power of engine `=K.E` of water flowing per sec
`=(1)/(2)m upsilon^(2)=(1)/(2)xx200xx2^(2)=400W`