How to Calculate Work Done in an Adiabatic Process in a Carnot Cycle?

schvetz
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Hey. I'm supposed to calculate the work done in an adiabatic process, B-C, and I only know the values of the temperatures and the volume in the first point (point B). It is not known if it is a mono or diatomic gas, therefore i don't know the value of gamma. I've tried T*V^(gamma-1)=K and the only conclusion I got is that Vc=5Vd... From A to B is isotermic and C to D as well, and I know the volume in A and B (1 liter and 5 liters respectively).
Sorry for the bad english.

Schvetz
 
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schvetz said:
Hey. I'm supposed to calculate the work done in an adiabatic process, B-C, and I only know the values of the temperatures and the volume in the first point (point B). It is not known if it is a mono or diatomic gas, therefore i don't know the value of gamma. I've tried T*V^(gamma-1)=K and the only conclusion I got is that Vc=5Vd... From A to B is isotermic and C to D as well, and I know the volume in A and B (1 liter and 5 liters respectively).
Sorry for the bad english.

Schvetz
Give us the entire problem. Does it refer to the gas as "air"? If so, what is the gamma of air?

AM
 
Ok, I'll try to translate the problem.
One mole of a gas describes a carnot cycle between the temperatures of 20ºC and 120ºC. ON the superior isothermic transformation, the initial volume is 1 liter and the final volume is 5 liters. Calculate the amount of heat exchanged between the cold source and the hot source and the work done in a cycle.
I hope you understand my translation.
 
Since this is the homework forum we would also like to see your attempt. We are not here to do your work for you or give you the answer.
 
schvetz said:
Ok, I'll try to translate the problem.
One mole of a gas describes a carnot cycle between the temperatures of 20ºC and 120ºC. ON the superior isothermic transformation, the initial volume is 1 liter and the final volume is 5 liters. Calculate the amount of heat exchanged between the cold source and the hot source and the work done in a cycle.
I hope you understand my translation.
Since it is a Carnot cycle, what can you say about the efficiency of this engine? What does it depend on? Can you work out Qh and Qc? Is there any heat exchanged between the hot and cold reservoirs during the two adiabatic parts of the process? You should be able to find the answer if you answer those questions.

AM
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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