MCQ
A pump motor is used to deliver water at a certain rate from a given pipe. To obtain twice as much water from the same pipe in the same time, power of the motor has to be increased to
- A$16$ times
- B$4$ times
- ✓$8 $ times
- D$2$ times
✓
Answer
Correct option: C.
$8 $ times
c
(c)Power of a pump$ = \frac{1}{2}\rho A{v^3}$
To get twice amount of water from same pipe v has to be made twice. So power is to be made $8$ times.
(c)Power of a pump$ = \frac{1}{2}\rho A{v^3}$
To get twice amount of water from same pipe v has to be made twice. So power is to be made $8$ times.
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