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3 years ago

(b) The efficiency of the pump which operates the fountain is 70%.

Physics

1 answer:

ruslelena [56]3 years ago

8 0

Answer:

Power supplied to the pump is 980000 W or 980 KW

Note: The question is incomplete. The complete question is given below:

On a day with no wind, a fountain in Switzerland propels 30000 kg of water per minute to a height of 140 metres.

a)Calculate the power used in raising the water?

b)The efficiency of the pump which operates the fountain is 70%

calculate the power supplied to the pump?

Explanation:

Efficiency = Power output/Power input * 100%

Power output = work done/ time

where work done = mass * acceleration due to gravity (g) * height

time = 1 minute = 60 seconds

mass of water = 30000 kg, height = 140 meters, g = 9.8 m/s²

Then, work done = 30000 * 140 * 9.8 = 41160000 J

Power output then = 41160000 J / 60 s

Power output = 686000 W

The power input can then be derived from the formula of efficiency

Power input = (Power output * 100)/Efficiency

Power input = (100 * 686000) / 70

Power input = 980000 W

Therefore, power supplied to the pump is 980000 W or 980 KW

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