Helmholtz Free Energy Calculator
Compute Helmholtz free energy F = U − TS.
Input Data
Internal Energy J
J
Temperature K
K
Entropy J Per K
J/K
Results
F = U − TS.
400J
T·S.
600J
F/T (useful at fixed T).
1.3333333333J/K
At a glance:F = U − TS (maximum useful work at constant T,V). Complements gibbs-free-energy and internal-energy.
Formula
F = U − T·S.
$$F = U - TS, \quad dF = -S\,dT - P\,dV, \quad S = -\left(\frac{\partial F}{\partial T}\right)_V, \quad P = -\left(\frac{\partial F}{\partial V}\right)_T$$How to Use
- Enter U, T and S.
- The tool returns F and TS.
Case Studies
U=1000, T=300, S=2
F = 400 J.
FAQ
Helmholtz vs Gibbs?
F is at constant T,V; G = U−TS+pV at constant T,p.
Related Tools
References
Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.