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A pump uses 1g of a mixture of petrol and alcohol in the ratio 4:1 by mass to raise 1000 kg of water from a...

A pump uses 1g of a mixture of petrol and alcohol in the ratio 4:1 by mass to raise 1000 kg of water from a well 200m deep.
i) How much energy is given by 1g of mixture?
ii) If the pump is 40% efficient, what mass of this mixture is needed to raise the water? (1g of alcohol = 7000J, of petrol= 48000J)

Answers


Wilfred
i)
1/5 g of alcohol will give 2.7 x 104J
4/5 of petrol will give 3.84 x 104 J
therefore, 1g of mixture gives
= 5.4 x 103 + 38.4 x 103J
= 43. 8 x 103J

ii)
w.d = mgh = 1000 x 200 x 10 = 2 x 106
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Wilfykil answered the question on March 26, 2019 at 11:56

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