scottymartin1992
New member
- Joined
- Mar 7, 2020
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if the fuel consumption of a car, travelling at a steady 60mph, is 20mpg what is the power produced by the petrol being burnt in the engine? (assume that the density of petrol is 0.84kg/l and the heat of combustion of petrol is 47,302kj/kg)
I was unsure so i worked out the total petrol used in a hour in litres. multipled that by 0.84 to convert it to kg, multiplied that by the combustion value. i then converted that value to J instead of KJ. divided that vaule by 3,600 (seconds in a hour) to get around 150k watts power output which seems about right for a car engine.
not sure if this post is in the right place sorry if its not any help on this would be much appreciated!
I was unsure so i worked out the total petrol used in a hour in litres. multipled that by 0.84 to convert it to kg, multiplied that by the combustion value. i then converted that value to J instead of KJ. divided that vaule by 3,600 (seconds in a hour) to get around 150k watts power output which seems about right for a car engine.
not sure if this post is in the right place sorry if its not any help on this would be much appreciated!
