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mech-eng
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Homework Statement
a) [/B]There is a piston-cylinder arrangement; initial pressure is 200 kPa, initial volume is 0.04m^3. Volume of the gas increases to 0.1 m3 while the pressure remains constant, ie a constant pressure process. Calculate the work.
b) There is a piston-cylinder arrangement; initial pressure is 200 kPa, initial volume is 0.04m^3. Volume increases to 0.1 m3 while its temperature is constant, ie a constant temperature process.
c) There is a piston-cylinder arrangement; initial pressure is 200 kPa, initial volume is 0.04m^3. Final volume is 0.1 m3 but this time PV^1.3=constant during the process ie a polytropic process with n=1.3.
My question is: 1) Does constant pressure process always give the biggest work?
2) What polytropic exponent gives the biggest work?
3) What would be the case for a isentropic process with the same final volume?
4) How can we understand if the energy of the system increases or decreases, taking the
gas as a system?
Homework Equations
1) dw=Pdv; P1V1^n=P2V2^n[/B]
The Attempt at a Solution
1) [/B]
2) if 1 is correct analyse then the answer to 2 should be polytropic exponent is 0.
3) I do not know this now but let me wait for it. I can answer it later.
4) I am not sure if this can be determined because we do not know what energy is given to the system so that we could use the equation Q-W=ΔE
http://home.iitk.ac.in/~suller/lectures/lec5.htm
Thank you.
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