Definition
The Helmholtz energy is defined as:
where
- A is the Helmholtz free energy (SI: joules, CGS: ergs),
- U is the internal energy of the system (SI: joules, CGS: ergs),
- T is the absolute temperature (kelvins),
- S is the entropy (SI: joules per kelvin, CGS: ergs per kelvin).
The Helmholtz energy is the negative Legendre transform with respect to the entropy, S, of the fundamental relation in the energy representation, U(S, V, N). The natural variables of A are T, V, N.
Read more about this topic: Helmholtz Free Energy
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