Recent content by HalfManHalfAmazing

Solving for V ALSO ends up being a third order polynomial which I have no idea on how to solve.

Oh wow. So now the only thing changing is pressure! dG = VdP. So now I solve the VdW equation of state for Volume. Plug that in and then integrate with respect to pressure? I'm going to give that a whirl! thanks!

If that's the case, I get: (ab/V^2)N^3 - (a/V)N^2 + (Pb +kT)N = PV. Solving for N is going to be annoying, unless there's a trick here?

Okay so because dT and dP are zero, we only have dG = udN. or G = uN. Thus we solve the equation of state for N and we're set?

Homework Statement Calculate the Gibbs free energy for a van der Waals gas (up to an integration constant), assuming a fixed amount of material and temperature. Homework Equations P = \frac{NkT}{V-Nb} - \frac{aN^2}{V^2} dG = -SdT + VdP + udN (where u is the chemical potential) The...

Thanks guys, I got all the answers! For a) I found: Change in S total = C (0.026) For b) : dS = C (0.013) For c) : dS = 0

Okay. I found the expression for the entropy change of the solid in the first path: dS = C ln ( Tf/Ti ) and i see that the entropy change in the reservoir must be dS = dQ / 373. But is that as 'simple' as I can get the answers? Or can I actually dQ? Edit: I found a way get dQ: C = dQ/dT...

In response to Andrew Mason: Sorry I'm having a little trouble understanding this concept of entropy change. When we have the entropy change of changing temperture, we just throw in the initial temperature of the object to the equation dS = dQ/T? Don't need need to integrate? If we just solve...

Homework Statement A solid with constant heat capacity is warmed from 20 C to 100 C in 3 different ways: a) by placing it in contact with a large reservoir at 100 C b) by placing it first in cantact with a large reservoir at 50 C until it reaches that temperature and then in contact with a...

Is the entropy of a 2 state system with 1 state with energy 0 equal to 0?

If I have a 2 state system with energy levels of the 2 states to be 0 and V. I find the partition function to be Z = 1 + e^(-V/kT). Am I correct? If so, does that not mean the average energy is V? and thus the entropy is 0? This doesn't make sense, how is the entropy of a 2 state system (when 1...

The thing with astro is, if you don't like stat-mech there is ZERO way astro is possible!

52% is horrible. like it's as bad as you can do without being kicked out of the school. looking back 8 months, i just don't understand how i did that poorly

Astrophysics! It's practially all the rest of the undergraduate courses thrown into one! If you have trouble with ANY of the others, astro is infinitely more difficult!

Hello, I am a third year physics student (at UBC in Canada) and I am wondering what are my options for the future. My second year average was something like 52% (I was mildly depressed at the time) and have boosted my grades over the year to just under 80%. I am looking to start getting some...