SOLUTION: An engine burns 1.4 kg of gasoline per hour and yields 3.5 kW of power. Calculate the efficiency of the engine when the heating value of gasoline is 43 MJ/kg. PLEASE HELP

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Question 402686: An engine burns 1.4 kg of gasoline per hour and yields 3.5 kW of power.
Calculate the efficiency of the engine when the heating value of gasoline is
43 MJ/kg.
PLEASE HELP
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the heat energy in the gasoline is ___ (1.4 kg) * (43 MJ/kg) = 60.2 MJ

one Watt is one Joule per second
3600 sec in an hr

power generated is ___ (3.5 kW) * (3600 sec) = 12.6 MJ

efficiency is ___ (12.6 MJ) / (60.2 MJ) ___ expressed as a percent