Calculating Internal Energy Change: Path 2 of Carnot Cycle Question

AI Thread Summary
The discussion focuses on calculating the change in internal energy of a gas along path 2 of a Carnot cycle, which involves a pressure reduction at constant volume and an expansion at constant pressure. The user attempts to apply the first law of thermodynamics, ΔE=Q-W, but struggles to determine the heat transfer (Q) due to a lack of specific values for heat capacities (Cv and Cp). They have successfully calculated the work done along path 1 but are uncertain how to apply similar reasoning to path 2 without additional data. The conversation emphasizes the need for understanding isochoric and isobaric processes to find the required values. Ultimately, the challenge lies in calculating Q without the necessary parameters.
Munir M
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Homework Statement


A gas is to be expanded from initial stage i to final stage f along either path 1 or path 2 on a p-V diagram. Path 1 consists of three steps: an isothermal expansion(work is 23J in magnitude), an adiabatic expansion(work is 35J in magnitude), and another isothermal expansion (work is 16J in magnitude). Path 2 consists of two steps: a pressure reduction at constant volume and an expansion at constant pressure. What is the change in the internal energy of the gas along path 2?

Homework Equations


ΔE=Q-W[/B]
W=nRTln(Vf/Vi)
W=∫PdV


The Attempt at a Solution


I added up the values from path 1 to be the work done, assuming that like a hess cycle the work done is same regardless of the path taken. I don't know how to get a value of Q as I don't know which equations out there work with isochoric and isobaric conditions.
 
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I found equations for isobaric and isochoric conditions. Q=nCpΔT and Q=nCvΔT. I still don't know how to solve it as none of the values for Cv and Cp are provided.
 
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