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 Advanced Thermodynamics Advanced Thermodynamics Physics Help Forum Mar 4th 2010, 03:27 PM #1 Junior Member   Join Date: Feb 2010 Posts: 2 Density of State I have this question given to me in my physics course to help with studying, but I'm a bit stuck on how to tackle it. The number of microstates in a system with energy between E and E+delE if an isolated system of N particles in a volume V is represented by this: g(E)delE = c(V-bN)^N * (E+(N^2a)/V)^(3N/2)*delE a, b, and c are constants, while del is the delta operator. (a) Determine the entropy of the system as a function of E, V, and N. (b) Determine the temperature T as a function of E, V, and N (c) Determine the energy in terms of T, V, and N. (d) What is the pressure as a function of T and p = N/V?   Apr 8th 2010, 03:38 PM #2 Senior Member   Join Date: Mar 2010 Location: Lithuania Posts: 105 It seems to be distribution of real gas (van der Waals model). From the main equation of statistics S = k ln g(E) we get (1) S = kN ln [ (V-bN)(E+N^2a/V)^3/2 ]. 1/T = dS/dE 1/T = (3/2) kN/(E+N^2a/V) and T = (2/3) (E+N^2a/V)/kN. From this equation we get E E = (3/2) kNT - N^2a/V. From (1) expressing E and P = -(dE/dV) S=const we get P = kNT/(V-bN) - N^2a/V^2 or (P+N^2a/V^2)(V-bN) = kNT.  Tags density, state Thread Tools Show Printable Version Email this Page Display Modes Linear Mode Switch to Hybrid Mode Switch to Threaded Mode Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post Linder Thermodynamics and Fluid Mechanics 7 Aug 18th 2016 04:33 AM kelsiu Thermodynamics and Fluid Mechanics 4 Sep 18th 2014 05:56 AM s3a Atomic and Solid State Physics 3 Oct 8th 2011 11:44 PM rimor51 Advanced Thermodynamics 1 Mar 19th 2011 01:56 PM joker1 Electricity and Magnetism 0 Mar 15th 2009 12:32 PM