Question

A water pump raises 50 litres of water through a height of 25m in 5s. Calculate the power of the pump used (assuming 100% efficiency). (Take g = 10 N kg^-1 and density of water = 1000 kg m^-3).

April 9, 2024

Answer

Volume of water raised = 50 L and
50 L = 50 × 10^-3 m³

height = 25m

time spent = 5s

As we know,

Mass of water = Volume of water × density of water

Mass = $50 × 1000\over 1000$ = 50 kg

Power = $m × g × h \over time$

= $50 × 10 × 25 \over 5$

= 2500 W

Therefore, power of the pump is 2500W.

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