A geyser, operating on LPG (liquefied petroleum gas) heats water flowing at the rate of 3.0 litres per minute, from 27oC to 77oC. If the heat of combustion of LPG is , how much fuel in grams is consumed per minute?


Correct option is



Volume of water flowing per minute = 3.0 litres min – 1

                                 = 3000 cm3 min – 1

Density of water = 1 g cm – 3


Rise in  temperature = 77 – 27 = 50oC

Specific heat of water = 4200 J 



Now, heat of combustion of LPG 






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