Recent content by publius10

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    Does Entropy Change When a Gas Cylinder is Raised to Vertical?

    jk it was the easiest exam of all time.o_O
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    Does Entropy Change When a Gas Cylinder is Raised to Vertical?

    Haha thanks for all your effort - this is a qual practice problem from Caltech - my qual is tomorrow. Point being, this is supposed to be solvable in 30 min, so I may be screwed. Anyway your equation looks like what I got - impossible to solve for general γ. Maybe I'll go back to the chemical...
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    Does Entropy Change When a Gas Cylinder is Raised to Vertical?

    Thanks for the detailed response - it makes more sense now, but.. ##P\propto\rho^\gamma\rightarrow P'\propto\rho^{\gamma-1}\rho'\rightarrow -\rho g\propto\rho^{\gamma-1}\rho'\rightarrow\rho'\propto-\rho^{2-\gamma}\rightarrow\rho\sim(-z)^{\frac{1}{\gamma-1}}=(C-Az)^{3/2}## for γ=5/3, where C is...
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    Does Entropy Change When a Gas Cylinder is Raised to Vertical?

    Ok I see the distinction between adiabatic and isentropic from wikipedia, but this process is reversible since you can just as easily place the cylinder back and it will return to its original state. Well this was what I was doing with the density distribution - clearly it is more dense toward...
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    Does Entropy Change When a Gas Cylinder is Raised to Vertical?

    1. I don't think it makes sense to ask for the temperature change if the temperature is not uniform, plus I think it has to be - in equilibrium. Otherwise the particles would just keep exchanging energy until they.. reached equilibrium. 2-4. For the entropy part, the problem also asks to "note...
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    Does Entropy Change When a Gas Cylinder is Raised to Vertical?

    Homework Statement A thin, closed, insulated cylinder of length L, filled with ideal gas (temperature T, mass M, total amount 1 mole) lies on a table. It is very gently raised to the vertical, after which equilibrium is reestablished. Does the entropy change? What is the temperature change (to...
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