Register to reply

Calculating Entropy of a Star using Heat Capacity

by khfrekek92
Tags: energy, entropy, star, temperature
Share this thread:
khfrekek92
#1
Feb6-12, 05:04 PM
P: 76
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...

Thanks in advance!
Phys.Org News Partner Science news on Phys.org
FIXD tells car drivers via smartphone what is wrong
Team pioneers strategy for creating new materials
Team defines new biodiversity metric
phyzguy
#2
Feb6-12, 05:50 PM
P: 2,179
Since a star is close to being an ideal gas, you should be able to use the Sackur-Tetrode equation to calculate its entropy.

http://en.wikipedia.org/wiki/Sackur%...trode_equation
khfrekek92
#3
Feb6-12, 06:18 PM
P: 76
That is what I was thinking too, but the problem specifically states that you need to use the heat capacity to determine the Entropy. :(


Register to reply

Related Discussions
Calculating molar specific heat capacity at constant volume and constant pressure Introductory Physics Homework 0
The difference between the entropy and the heat capacity? they are very similar Mechanical Engineering 19
Heat and Internal Energy and Heat and Temperature Change: Specific Heat Capacity Advanced Physics Homework 4
Should I average the following when calculating heat capacity? Introductory Physics Homework 6