Air expands steadily through a turbine from 6 bar, 800 K to 1 bar, 520 K. During the expansion, heat transfer from air to the surroundings at 300 K is 10 kJ/kg air. Neglect the changes in kinetic and potential energies and evaluate the irreversibility per kg air. Assume air to behave as an ideal gas with c

I = 100 C p ln T 2 - Rln P 2 + 300 T 1 P 1 10

I = 300CplnT2 - RlnP2 + 10T1P1300

I = 100CplnT2 - RlnP2 + 300T1P110

I = 300CplnT1 - RlnP2 + 10T2T1300

Air expands steadily through a turbine from 6 bar, 800 K to 1 bar, 520

1.	Air expands steadily through a turbine from 6 bar, 800 K to 1 bar, 520 K. During the expansion, heat transfer from air to the surroundings at 300 K is 10 kJ/kg air. Neglect the changes in kinetic and potential energies and evaluate the irreversibility per kg air. Assume air to behave as an ideal gas with c
A.	<table><tr><td rowspan="2">I = 300</td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-oparen-h1.gif"></td><td rowspan="2">C<sub>p</sub>ln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>T<sub>2</sub></center></td><td rowspan="2"> - Rln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>P<sub>2</sub></center></td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-cparen-h1.gif"></td><td rowspan="2"> + </td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>10</center></td></tr><tr><td style="text-align: center;">T<sub>1</sub></td><td style="text-align: center;">P<sub>1</sub></td><td style="text-align: center;">300</td></tr></table>
B.	<table><tr><td rowspan="2">I = 100</td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-oparen-h1.gif"></td><td rowspan="2">C<sub>p</sub>ln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>T<sub>2</sub></center></td><td rowspan="2"> - Rln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>P<sub>2</sub></center></td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-cparen-h1.gif"></td><td rowspan="2"> + </td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>300</center></td></tr><tr><td style="text-align: center;">T<sub>1</sub></td><td style="text-align: center;">P<sub>1</sub></td><td style="text-align: center;">10</td></tr></table>
C.	<table><tr><td rowspan="2">I = 300</td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-oparen-h1.gif"></td><td rowspan="2">C<sub>p</sub>ln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>T<sub>1</sub></center></td><td rowspan="2"> - Rln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>P<sub>2</sub></center></td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-cparen-h1.gif"></td><td rowspan="2"> + </td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>10</center></td></tr><tr><td style="text-align: center;">T<sub>2</sub></td><td style="text-align: center;">T<sub>1</sub></td><td style="text-align: center;">300</td></tr></table>
D.	<table><tr><td rowspan="2">I = 300</td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-oparen-h1.gif"></td><td rowspan="2">C<sub>p</sub>ln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>T<sub>1</sub></center></td><td rowspan="2"> - Rln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>P<sub>1</sub></center></td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-cparen-h1.gif"></td><td rowspan="2"> + </td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>1</center></td></tr><tr><td style="text-align: center;">T<sub>2</sub></td><td style="text-align: center;">P<sub>2</sub></td><td style="text-align: center;">3</td></tr></table>
Answer» B. <table><tr><td rowspan="2">I = 100</td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-oparen-h1.gif"></td><td rowspan="2">C<sub>p</sub>ln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>T<sub>2</sub></center></td><td rowspan="2"> - Rln</td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>P<sub>2</sub></center></td><td rowspan="2"><img src="https://www.indiabix.com/_files/images/data-interpretation/common/15-sym-cparen-h1.gif"></td><td rowspan="2"> + </td><td style="border-bottom:1px solid #000000;vertical-align:bottom;padding-bottom:2px;"><center>300</center></td></tr><tr><td style="text-align: center;">T<sub>1</sub></td><td style="text-align: center;">P<sub>1</sub></td><td style="text-align: center;">10</td></tr></table>

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