How Does a Gasoline Engine Manage Heat?

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A gasoline engine with a power output of 180 kW and a thermal efficiency of 28% requires a heat supply of approximately 643 kW per second to operate. Since only 28% of the supplied energy is converted to mechanical energy, the remaining 72% is discarded as waste heat. To find the heat discarded, one can calculate 72% of the total heat supplied. Understanding thermal efficiency is crucial for solving such problems in physics. This discussion emphasizes the importance of applying the concept of thermal efficiency to determine energy inputs and outputs in engine operations.
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hey what's up guys, I need some help solving a homework problem for physics...
here is the question.
A gasonline engine has a power output of 180 kW (241hp). Its thermal efficiency is 28%.

a) How much heat must be supplied to the engine per second?
b) How much heat is discarded by the engine per second?

I know this is probably a simple question, but I am kind of having a hard time with this chapter. I know that thermal efficiency is equal to work/Qh...and after that...i need a little help. Thanks for any help.
 
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Can Anyone help? Thats all that was given in the question...
 
ziddy83 said:
hey what's up guys, I need some help solving a homework problem for physics...
here is the question.
A gasonline engine has a power output of 180 kW (241hp). Its thermal efficiency is 28%.

a) How much heat must be supplied to the engine per second?
b) How much heat is discarded by the engine per second?

I know this is probably a simple question, but I am kind of having a hard time with this chapter. I know that thermal efficiency is equal to work/Qh...and after that...i need a little help. Thanks for any help.

If only 28% of the energy supplied is converted to mechanical energy, what percent is not converted to mechanical energy? Power is just the rate of energy supplied/converted, so ask the same question about the power. Work your way back to figure out how much power must be supplied.
 

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