Q129 / 160 · TS EAMCET 2021 (05 Aug Shift 2) · Physics

A water pump rated $600 W,$ has an efficiency of $95 % .$ If it is used to raise water through vertical distance of $60 m .$ The volume of water drawn in $20$ minutes, is [Use density of water $= 1000 kg m^{- 3}, g = 10 m / s^{2}$ ]

Solution

Power of water pump to lift water is,

P_{p} = \frac{ρ V g h}{t}

,
Effective power to raise water is given by,

P_{p} = η P_{R a t e d}

\Rightarrow P_{p} = 0.95 \times 600 = 570 W

\Rightarrow \frac{ρ V g h}{t} = 570

\Rightarrow \frac{1000 \times V \times 10 \times 60}{20 \times 60} = 570

\Rightarrow V = \frac{570 \times 20 \times 60}{1000 \times 10 \times 60} = 1.14 m^{3}

Hence, the correct answer is option: 'A'.