Calculating work output of an engine, using ideal gas

AI Thread Summary
The discussion revolves around calculating the work output of a Stirling engine using ideal gas principles. The engine operates with a specific amount of gas and temperature differences between reservoirs, requiring the calculation of heat input (Qh) and heat output (Qc). Participants express confusion about how to derive Qh and Qc from the given data and emphasize the importance of understanding the problem's requirements. Suggestions include drawing a PV diagram to visualize the Stirling cycle, which could aid in solving the problem. Clarification on the specific calculations needed is sought to proceed effectively.
lagwagon555
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Homework Statement



A model Stirling engine uses n = 8.04 × 10–3 mol of gas (assumed to be ideal) as a working substance. It operates between a high temperature reservoir at TH = 98.0 °C and a low temperature reservoir at Tc = 25.0 °C. The volume of its working substance doubles during each expansion stroke. It runs at a rate of 0.7 cycles per second. Assume the engine is ideal.

How much work does the engine do per cycle?

Homework Equations



W(eng) = Qh - Qc

The Attempt at a Solution



I assume that you have to find the energy input and output by using the temperatures, and the mol of gas, taking into account it's an ideal gas. However, taking the first step is the problem. I have no clue how to work out Qh and Qc, from the given data. Or perhaps there's some other way you have to solve it?
 
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What does the problem actually ask you to calculate? You don't seem to have included that in the problem statement... does it actually say you need to find the energy input and output, or are you just guessing at that?
 
I can't believe I forgot to put that question in. I edited the original - sorry about that.
 
Have you drawn the PV diagram for an idealized Stirling cycle? If not, that would help with figuring out what's going on.
 

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