# How to calculate Laws of Thermal Radiation

1. Feb 27, 2012

### JayWilks

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

2. Feb 27, 2012

### LawrenceC

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.

3. Feb 27, 2012

### JayWilks

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.