Question

On a day with no wind, a fountain in switzerland propels 30,000 kg of water per minute to a height of 140m. Calculate the power used in raising the water. Show your working

Answer 1

mass of water per minutes propelled by the fountain = 30000 kg/min

= 30000 kg/60 sec

= 500 kg/s

so, mass of water after time t , M = 500t kg

potential energy of water , U = Mgh

here, M = 500t kg , g = 10m/s² [ acceleration due to gravity ] and h = 140m

= 500t kg × 10m/s² × 140m

= 700000t J

power used in raising water = energy/time

= 700000t/t = 700000 watt

= 700kwatt

hence, answer is 700 kwatt