Calculating Entropy of a Star using Heat Capacity

AI Thread Summary
The discussion focuses on calculating the entropy of a star using its heat capacity, given as C=-3*k/2. The user attempts to integrate the equation dS=C*dT/T, resulting in S=-(3/2)*k*ln(tf/ti)+C, but encounters difficulties when trying to solve for S, particularly at zero temperature. Another participant suggests using the Sackur-Tetrode equation, noting that stars behave like ideal gases. However, the original problem specifically requires the use of heat capacity for the entropy calculation. The conversation highlights the challenge of applying theoretical equations in practical scenarios.
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Homework Statement


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).


Homework Equations


dS=C*dT/T



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...

Thanks in advance!
 
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That is what I was thinking too, but the problem specifically states that you need to use the heat capacity to determine the Entropy. :(
 

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