Star A has a temperature of 9000 K while Star B has a temperature 3000 K. If the two stars are the same size, according to the Stefan-Boltzmann law, how much brighter is star A than star B?

Star A is this many times (9000)^4 x [4 π R^2 σ]  brighter than Star B =  (3000)^4 x [4 π R^2 σ]

Explanation:

In accordance with the Stefan-Boltzmann Law,

L = 4 π R^2 σ Τ^4

(Where L = is the energy emitted out by star i.e., Brightness, R = Radius of the star, σ = 5.67 x 10^-8 Stefan-Boltzmann Constant and T is the temperature of the star)

Star A = (9000)^4 x [4 π R^2 σ]

Star B =  (3000)^4 x [4 π R^2 σ]

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