An electric pump raises of water from the ground into an overhead tank above in
PHYSICS · Multi-part · CBSE · Physics · Work and Energy · Work and Energy
Problem
An electric pump raises 500kg of water from the ground into an overhead tank 15m above in 50s. A second pump of the same design raises the same amount of water through the same height in 80s.
(i) Write the expression for the average power developed by a pump while lifting water.
(ii) Calculate the average power output of each pump. Take g=9.8m s−2.
(iii) Determine the ratio of the average powers of the two pumps.
(iv) If both pumps momentarily deliver water at the same rate during start-up, explain why their instantaneous power outputs can still be equal even though their average powers differ.