Statistical weight (thermodynamics)

Click For Summary
SUMMARY

The discussion focuses on deriving the equation of state relating pressure (P), volume (V), number of particles (N), and temperature (T) using statistical mechanics. The equation of state is represented as P/T = (ds/dV)E,N, where s = klnΩ and Ω = CebNV2(EV)N. The user initially derived P = k2bNVT but was advised to reconsider the derivative due to the presence of V in the logarithm, which requires careful differentiation. The terms E and N in (ds/dV)E,N indicate that energy (E) and number of particles (N) are held constant during differentiation.

PREREQUISITES
  • Understanding of statistical mechanics concepts, particularly the equation of state.
  • Familiarity with thermodynamic variables: pressure (P), volume (V), number of particles (N), and temperature (T).
  • Knowledge of derivatives and their application in thermodynamics.
  • Experience with logarithmic functions and their differentiation.
NEXT STEPS
  • Review the derivation of the equation of state in statistical mechanics.
  • Study the implications of holding variables constant in thermodynamic derivatives.
  • Learn about the role of constants in statistical weight equations, specifically C and b.
  • Explore advanced topics in thermodynamics, such as Maxwell's relations and their applications.
USEFUL FOR

Students and professionals in physics and engineering, particularly those studying thermodynamics and statistical mechanics, will benefit from this discussion. It is especially relevant for those working on equations of state and thermodynamic properties.

quietrain
Messages
648
Reaction score
2

Homework Statement


find the equation of state which gives the relationship between P , V , N and T

C and b are constants

Ω = CebNV2(EV)N

Homework Equations



P/T = (ds/dV)E,N

The Attempt at a Solution



so i just use s = klnΩ ?

then i get ds/dV = k2bNV

so P = k2bNVT ? that's it?

btw, what does the E and N in (ds/dV)E,N tells me? is it mean keep E and N constant? or the differential is specified by the terms E and N?

thanks!
 
Physics news on Phys.org
quietrain said:

Homework Statement


find the equation of state which gives the relationship between P , V , N and T

C and b are constants

Ω = CebNV2(EV)N

Homework Equations



P/T = (ds/dV)E,N

The Attempt at a Solution



so i just use s = klnΩ ?

then i get ds/dV = k2bNV

so P = k2bNVT ? that's it?

That seems like the correct method, but double check your derivative. You have a factor of V inside the logarithm, so you should have a second term in your derivative corresponding to differentiating the log(EV) and not V^2


btw, what does the E and N in (ds/dV)E,N tells me? is it mean keep E and N constant?

Yes, that is what it means.
 
ah i see thank you!
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
1
Views
1K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 11 ·
Replies
11
Views
1K
Replies
3
Views
2K
  • · Replies 42 ·
2
Replies
42
Views
6K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 13 ·
Replies
13
Views
2K