Question

An engine pumps water through a hose pipe. Water passes through the pipe and leaves it with a velocity of $1$ m/s. The mass per unit length of water in the pipe is $100$ kg/ m. What is the power of the engine?

• A. $100$ W
• B. $400$ W
• C. $200$ W
• D. $800$ W

Answer 1

The correct option is A $100$ W

mass per unit length of water, $\mu =100kg/m$

velocity of water $V=1m/s$

Power of the engine, $p=\mu v^3$

$=100\times 1^3$

$=100W$

Hence, option $A$ is the correct answer.