(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I have to calculate the change in a protostar's thermal energy [tex]\Delta E_{term}[/tex] on a year.

I am given the protostar's luminosity [tex]L=3,5\cdot 10^{28}\,W[/tex]

Furthermore I am told that the energy that the star radiates comes from the lost potential energy under the star's contraction.

2. Relevant equations

The virial Theorem: [tex]E_{total}=E_{kin}+E_{pot}=\frac{1}{2}E_{pot}=-E_{kin}[/tex]

3. The attempt at a solution

I can calculate the "radiated" (lost) energy: [tex]3,5\cdot 10^{28} W\cdot 365,25\cdot 24\cdot 60^2 \frac{s}{y}=1,105\cdot 10^{36} J[/tex]

But I don't know how if this is right or how to get to it by arguing from the virial theorem.

I really hope you can help me.

Best regards.

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# Homework Help: Protostar - Thermal energy change

Can you offer guidance or do you also need help?

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