In a steam engine, the boiler temp is at 170C and cold temp reservoir is at 25 C
ID: 2289411 • Letter: I
Question
In a steam engine, the boiler temp is at 170C and cold temp reservoir is at 25 C. Find the maximum efficiency that this engine can attain. And in a time over which the engine removes 10.0 kJ of heat from the boiler, what is the minimum energy that must be discharged into cold temp reservoir? In a steam engine, the boiler temp is at 170C and cold temp reservoir is at 25 C. Find the maximum efficiency that this engine can attain. And in a time over which the engine removes 10.0 kJ of heat from the boiler, what is the minimum energy that must be discharged into cold temp reservoir? Find the maximum efficiency that this engine can attain. And in a time over which the engine removes 10.0 kJ of heat from the boiler, what is the minimum energy that must be discharged into cold temp reservoir?Explanation / Answer
here efficiency e of heat engine is given by e = 1-T2/T1
T2 = 25 +273
T1 = 170 + 273
e = (1-(25+273)/(170+273)
e = 0.3273 or 32.73 % is the max effficiency of heat engine
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now use efficiency is also given by e = W/Q
where W is work done and
Q is heat eenrgy
so W = e Q
W 0.3273 * 10000
W = 3.272 kJ