# Adiabatic process in carnot cycle

1. Jun 29, 2009

### schvetz

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).

Schvetz

2. Jun 29, 2009

### Andrew Mason

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

AM

3. Jun 29, 2009

### schvetz

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.

4. Jun 29, 2009

### djeitnstine

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.

5. Jun 30, 2009

### Andrew Mason

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