Entropy And Energy Representation

In summary, to go from the entropy of a system, S(U,V,N), to its internal energy, U(S,V,N), for an ideal classical gas, we can use the equation U=N*(U/N)^(2/3)*exp[(2/3)*(S/(N*R)-c)]. This involves isolating ln(U/N), using e^() on both sides, and multiplying with N.
  • #1
hurz
7
0
How do I go from the entropy of a system, S(U,V,N), to its internal energy, U(S,V,N)?
For instance, for an ideal classical gas, we have

S=(3/2)N*R*ln(U/N) + N*R(V/N) + N*R*c

where R is the Boltzmann constant, N is the particle number, V is the volume and "c" is a constant.

How can I convert this to U(S,V,N) ?

The unswer is U=N*(U/N)^(2/3)*exp[(2/3)*(S/(N*R)-c)]

Regards,
hurz.
 
Science news on Phys.org
  • #2
This is just algebra. Isolate ln(U/N), use e^() on both sides and multiply with N.
 
  • #3
my bad. thanks!
 

Related to Entropy And Energy Representation

What is entropy and energy representation?

Entropy and energy representation is a concept in physics that explains the relationship between energy and disorder in a system. It is a measure of the amount of energy that is unavailable for work due to the randomness or disorder of a system.

How is entropy and energy representation related to the laws of thermodynamics?

Entropy and energy representation is closely related to the second law of thermodynamics, which states that the total entropy of a closed system will always increase over time. This means that energy will always flow from areas of higher energy to areas of lower energy, resulting in an increase in disorder or entropy.

What are some real-life examples of entropy and energy representation?

One example of entropy and energy representation is a car engine. As the fuel burns, it releases energy and produces heat, but some of this energy is lost as heat and cannot be used to do work. This results in an increase in entropy. Another example is a cup of hot coffee left on a table. The coffee will eventually cool down as its energy is transferred to the surrounding environment, resulting in an increase in entropy.

Can entropy and energy representation be reversed?

The second law of thermodynamics states that entropy will always increase, meaning that it cannot be reversed. However, it is possible to decrease the entropy of a system by adding external energy, such as in a refrigerator or a plant using photosynthesis.

How is entropy and energy representation used in other fields besides physics?

Entropy and energy representation is a fundamental concept in many fields, including chemistry, biology, and information theory. It is used to understand and predict the behavior of systems and processes in these fields. For example, it is used in chemistry to calculate the spontaneity of a reaction, and in information theory to measure the amount of disorder in a message or signal.

Similar threads

I Does Callen's Entropy Expression for a General Ideal Gas Contain an Error?
    • Thermodynamics
Replies
19
Views
1K
I Helmholtz entropy of ideal gas mixture is additive?
    • Thermodynamics
Replies
3
Views
1K
I How can the maximum entropy and minimum energy principles be physical?
    • Thermodynamics
Replies
13
Views
2K
Thermodynamic equation of differentials (and how to work with them)
    • Thermodynamics
Replies
1
Views
782
A Equilibrium, entropy, probability - Release of constraints
    • Thermodynamics
Replies
2
Views
863
I Understand the Thermodynamic Identity: Is This Correct?
    • Thermodynamics
Replies
3
Views
1K
Why does the entropy of a closed system remain constant in a reversible process?
    • Thermodynamics
Replies
10
Views
2K
I A calculation of microstates
    • Thermodynamics
Replies
7
Views
1K
I Focus Problem for Entropy Change in Irreversible Adiabatic Process
    • Thermodynamics
2
Replies
56
Views
3K
I Obtaining this form for molar energy under virial expansion (Callen)
    • Thermodynamics
Replies
23
Views
1K

Hot Threads

Recent Insights

Back
Top