Work & Equilibrium of Insulated Box: Why W=0?

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In the insulated box scenario, the work done (W) is considered zero because the system is isolated, meaning there is no heat transfer or external work acting on it. The piston is frictionless and thermally conducting, allowing for equilibrium without energy exchange with the surroundings. Since both sides of the piston are at the same temperature (400K) after equilibrium is reached, there is no net work done between the two air chambers. The absence of external forces and heat transfer confirms that W=0 for the entire system. Therefore, the conclusion that W=0 is valid in this context.
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Homework Statement



"An insulated box is initially divided by a frictionless, thermally conducting piston. One side of the piston is 1.5(m^3) of air at 400k, 4bar. The other side is 1.5(m^3) of air at 400K,2 bar
The piston is released and equilibrium is attained, with the piston experiencing no change of state"


the solution assumes W=0. why is this?

Homework Equations





The Attempt at a Solution

 
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What solution? You didn't post any solution.
 
dauto said:
What solution? You didn't post any solution.

here
 

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That's the work for the entire system, not the work between the two chambers. Since the entire system is in a isolated box, there is no external work or heat.
 

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