A fire engine must lift 30 kg of water a vertical distance o

A fire engine must lift 30 kg of water a vertical distance ot 20 m each second. What is the amount of power needed for the water pump for this fire hose?

Solution

Mass of water m = 30 kg

Vertical distance h = 20 m

Time t = 1 s

Work done W = mgh

                     = 30 kg x 9.8 m/s ² x20 m

                     = 5880 J

Power P = W / t

              = 5880 J / 1 s

              = 5880 watt

               = 5.88 kilowatt