Emissivity Dimensional Analysis

[mikekyrou]

Homework Statement

Does anyone know where can i find (book?) the dimensional analysis of emissivity?

Homework Equations

The Attempt at a Solution

 

[tiny-tim]

hi mikekyrou!

emissivity is a dimensionless ratio (i supppose it might be better called relative emissivity)

see http://en.wikipedia.org/wiki/Emissivity" …

The emissivity of a material (usually written ε or e) is the relative ability of it's [spelling!] surface to emit energy by radiation. It is the ratio of energy radiated by a particular material to energy radiated by a black body at the same temperature. A true black body would have an ε = 1 while any real object would have ε < 1. Emissivity is a dimensionless quantity.​

 

[mikekyrou]

Thanks for the reply tiny-tim. I know what is emissivity and i want to prove that emissivity is dimensionless. I know that is because is a ratio but i want to prove it through equations(dimensional analysis-using mass,length,time).

 

[tiny-tim]

but if it's a ratio of two things that are the same dimensionally, then it has to be dimensionless

 

[mikekyrou]

Yes i agree. But i want to prove how the emissivity formula is derived.

Have a look here: http://en.wikipedia.org/wiki/Dimensional_analysis

After this i hope that you will understand what i am looking to find.