Question

A pump on the ground floor of a building can pump up water to fill a tank of volume 30 m³ in 15 min. If the tank is 40 m above the ground, how much electric power is consumed by the pump. The efficiency of the pump is 30%.

Answer 1

30% of power =  \(\frac{W}{t}\) = \(\frac{mgh}{t}\) = \(\frac{Vρgh}{t}\)

\(\frac{30}{100} \times P\) = \(\frac{Vρgh}{t}\)

∴ p = 43.6 KW.