Answer to Question #2978 in Molecular Physics | Thermodynamics for Jack Tredrea
What is the equation for work done in a reversible isothermal process (processes 1 to 3 in this case)? My course tutor wrote down (P3V3)ln(V1/V3), what is this?
The expression of work for that process A=-nRT*ln(V3/V1) where V1-the initial volume, V3 -the final volume. From the equation of state, if our substance is a gas we can get an approximate value of the expansion work using the ideal gas equation of state pV=nRT Since T=const, we can say that nRT=p3V3 also from the properties of ln-function ln(V3/V1)=-ln(V1/V3) So we have A=p3V3*ln(V1/V3) that's exactly what ur teacher wrote.