# Calculating Entropy of a Star using Heat Capacity

1. ### khfrekek92

82
1. The problem statement, all variables and given/known data
Using the viral theorem, the heat capacity of a star is given as C=-3*k/2.
Using this, I need to calculate the entropy of a star in terms of the average temperature T, then in terms of U (total energy).

2. Relevant equations
dS=C*dT/T

3. The attempt at a solution
To solve for S, I integrated getting S=-(3/2)*k*ln(tf/ti)+C. How do I solve this for S? This function is undefined when Temperature is 0...