Question

Increasing internal energy of a system __________ the helmholtz free energy at constant $TS$.

• A. increases
• B. decreases
• C. remains constant
• D. none of these

Answer 1

Answer: (A)

increases

Helmholtz free energy is given by $A=U-TS$ where U=internal energy, T=temperature, S=entropy

When TS is constant

When internal energy increases, helmholtz free energy increases

When internal energy decreases, helmholtz free energy decreases (from the equation)