If a reciprocating pump having a mechanical efficiency of 75% delivers water at the rate of 80 kg/s with a head of 25 m, the brake power of the pump would be (take g = 9.81 m/s²)
- A14715 W
- B19620 W
- C25212 W
- DNone of aboveCorrect
Solution
Concept
Brake power of a pump
Formula
BP = ṁ g H/η
Step-by-step solution
1. Water power = ṁ g H = 80 × 9.81 × 25 = 19620 W. 2. Brake power = 19620/0.75 = 26160 W. 3. This is not among A–C, so the answer is "None of above".
Explanation
19620 W is only the water power (option B).
Why the other options are wrong
A and C do not follow from the data.
Shortcut
BP = 19620/0.75 = 26160 W.
Common mistake
Choosing 19620 W (water power).
Correct answer: D) None of above