A water pump driven by petrol raises water at a rate of 0.5 m3 / min from a depth of 30 m . If the pump is 70 % efficient, what power is developed by the engine?

Question

A water pump driven by petrol raises water at a rate of 0.5 m3 / min from a depth of 30 m . If the pump is 70 % efficient, what power is developed by the engine? (A) 1750 W (B) 2450 W (C) 3500 W (D) 7000 W

Tardigrade Admin · Accepted Answer

Useful work done/sec. P text out =(( text mass / sec )) × g h=(0.5 × 1000 × 9.8 × 30/60) Power of the engine (P text out /η) =(0.5 × 1000 × 9.8 × 30/60) × (100/70)=3500 watt.

Q. A water pump driven by petrol raises water at a rate of $0.5 m^{3} / min$ from a depth of $30 m$ . If the pump is $70%$ efficient, what power is developed by the engine?

1750 W

2450 W

3500 W

7000 W

Useful work done/sec.
$P_{out} = (\frac{mass}{s e c}) \times g h = \frac{0.5 \times 1000 \times 9.8 \times 30}{60}$
Power of the engine $\frac{P _{out}}{η}$
$= \frac{0.5 \times 1000 \times 9.8 \times 30}{60} \times \frac{100}{70} = 3500$ watt.

Q. A water pump driven by petrol raises water at a rate of 0.5m3/min from a depth of 30m . If the pump is 70% efficient, what power is developed by the engine?