I was wondering in class today how I could determine the temperature of a filament in an incandescent light bulb? Mainly then so I could determine the thermal energy outputted through radiation. So after school I used a test circuit. I started with the Stefan-Boltzmann law which is Q = (ε)(σ)(T4)(A)(t) First I substituted 60s into the equation as my time, 0.191 as my emissivity constant and for Area I measured 1.1x10-5m2 So finally I got Q = (60s)(0.191)(5.670367 W/m2K4*10-8)(1.1x10-5m2)(T4) ⇒ Q = 7.1480646402×10-12(T4) I am so close to my answer but I simply don't know how to figure out how to get temperature from my knowledge of circuits! I had my powersource to stay at 4.0 Volts and my lightbulb was 1.44 Watts type so we just turn that into 1.44W = 4.0V(I) ⇒ (1.44W/4.0V) = I ⇒ 0.36 amperes = I and for resistance it is just 4.0V = 0.36A(R) ⇒ 4.0V/0.36A = R ⇒ 11Ω ≅ R. From there I have no idea of how to determine the temperature of the filament so any and all help would be appreciated, thank you!