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## Homework Statement

I need some help with this problem:

A model Stirling engine uses n = 7.44 × 10

^{–3}mol of gas (assumed to be ideal) as a working substance. It operates between a high temperature reservoir at T

_{H}= 95.0°C and a low temperature reservoir at T

_{c}= 24.0°C. The volume of its working substance doubles during each expansion stroke. It runs at a rate of 0.6 cycles per second. Assume the engine is ideal.

How much Work does the engine do per cycle (include the sign)?

## Homework Equations

[tex]W=nRT ln \frac{V_i}{V_f}[/tex]

## The Attempt at a Solution

Using the formula above I get

(7.44 × 10

^{-3})(8.314) T ln (v

_{i}/2v

_{i})

But I don't know how to continue since I don't know the value for the initial volume or temprature and I don't know how to find them... I mean for the temprature at least, I'm given two different tempratures T

_{H}and T

_{c}and I don't see which one to use!