3 Use \(g\) as \(9.8 \mathrm {~ms} ^ { - 2 }\) in this question. A pump is used to pump water out of a pool.
The pump raises the water through a vertical distance of 5 metres and then ejects it through a pipe. The pump works at a constant rate of 400 W
Over a period of 50 seconds, 300 litres of water are pumped out of the pool and the water is ejected with speed \(v \mathrm {~m} \mathrm {~s} ^ { - 1 }\) The mass of 1 litre of water is 1 kg
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1. Find the gain in the potential energy of the 300 litres of water.
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2. \(\quad\) Calculate \(v\)