Chapter-5 2 nd Law
Chapter-5 2 nd Law
Chapter-5 2 nd Law
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Thermal efficiency<br />
Desired output<br />
In general performance = =<br />
required input<br />
What I Get<br />
What I pay for<br />
In heat engines the desired output = net work output =<br />
W<br />
net , out<br />
the required input = heat supplied to system =<br />
Qin<br />
Thermal<br />
efficiency<br />
<br />
th<br />
or<br />
<br />
<br />
W<br />
th<br />
net,<br />
out<br />
Q<br />
<br />
in<br />
W<br />
net,<br />
out<br />
Q<br />
<br />
H<br />
Q<br />
in<br />
Q<br />
Q<br />
in<br />
out<br />
Q<br />
1<br />
Q<br />
L<br />
H<br />
1<br />
Q<br />
Q<br />
out<br />
in<br />
can Q out 0?<br />
No, because a) the cycle will not be complete!<br />
b)violates Kelvin-Plank statement.
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