How to calculate Laws of Thermal Radiation

AI Thread Summary
To calculate the power emitted per square meter by Star X, use the Stefan-Boltzmann Law, which involves raising the surface temperature (10,000 K) to the fourth power and multiplying by the Stefan-Boltzmann constant. For the dominant wavelength of electromagnetic radiation emitted by Star X, apply Wien's Law, which relates temperature to wavelength. The discussion highlights confusion around applying these laws and inputting the formulas into a calculator. The user expresses difficulty in understanding the concepts and seeks clarification on the calculations. Mastery of these laws is essential for accurate thermal radiation calculations.
JayWilks
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1. Star X has a surface temperature of 10,000 K. How much power does it emit per square meter? Enter numbers only. Do not enter units (watt/m2 is assumed)
2. Star X has a surface temperature of 10,000 K. What is the wavelength of the dominate electromagnetic radiation that Star X emits? Enter numbers only. Do not enter units (nanometers, nm is assumed)
I know that I'm supposed to use Stefan-Boltzmann Law for the first question and Wien's Law for the second but I have no idea on how to go about it. Any help would be truly appreciated
 
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Radiation emitted is computed for things here on Earth by multiplying the absolute temperature to the 4th power by the Stephan-Boltzmann constant and the emissivity. If you assume the star is a black body, the emissivity is unity.
 
LawrenceC said:
Radiation emitted is computed for things here on Earth by multiplying the absolute temperature to the 4th power by the Stephan-Boltzmann constant and the emissivity. If you assume the star is a black body, the emissivity is unity.

I was doing okay in this course until this lesson. I am taking this class online and this all seems way over my head, even what you just stated to me I'm having a hard time understanding. I think I found the formulas to get my answers but I don't know how or if they can be inputted to a calculator.
 

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