How to visualize entropy in thermodynamics

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vijay123
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entropy is the measure of disorder...but i just cannot visualize it in a practical standpoint...i mean...the disorder taking place with soo many particles when heated and yet all i know is that s=q/t...can anyone explain this concept better to me?

one more question...how does one prove using statistical mechanics that
s=(boltzmann's constant)lnw...were w is the number of macrostates...

i was tryng to do calculus based entropy probelms...but can do them in refrence to s=(boltzmann's constant)lnw, by counting the number of macrostates available??

and is it possible to find th number of macrostates by equating (boltzmann's constant)lnw=q/t...is this a very large number?
 
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vijay123 said:
one more question...how does one prove using statistical mechanics that
s=(boltzmann's constant)lnw...were w is the number of macrostates...
Entropy of a composite system is given by:
S* = SA + SA'-----(1)
Number of accessible states to A* is:
W* = WAWA'------(2)

S*,SA, SA' are entropies of composite system A*, A and A' respectively(A* composed of A and A').
The entropy is a "state" function.
For (1) & (2) to hold good simultaneously, what should be the nature of this function?
 
vijay123 said:
entropy is the measure of disorder...but i just cannot visualize it in a practical standpoint...i mean...the disorder taking place with soo many particles when heated and yet all i know is that s=q/t...can anyone explain this concept better to me?

one more question...how does one prove using statistical mechanics that
s=(boltzmann's constant)lnw...were w is the number of macrostates...

i was tryng to do calculus based entropy probelms...but can do them in refrence to s=(boltzmann's constant)lnw, by counting the number of macrostates available??

and is it possible to find th number of macrostates by equating (boltzmann's constant)lnw=q/t...is this a very large number?
Use the thermodynamic definition of entropy and forget about the concept of disorder: dS = dQ/T

AM
 
You'll need to use the definition of temperature [tex]\frac{1}{k_{B}T} = \frac{\partial\ln\Omega}{\partial U}[/tex] as well.
 
...though you might want to show where that comes from, it might be kinda easy otherwise...