(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A tungsten filament in a lamp is heated to a temperature of 2.30 x 10^3 K by an electric current. The tungsten has an emissivity of 0.31. What is the surface area of the filament if the lamp delivers 35.0 W of power?

2. Relevant equationsStefan's Law

(a greek letter that looks like P?) P(net)=ekAT^4

3. The attempt at a solution

35.0=0.31(5.670x10^-8 w/m^2*K^4)(2.30*10^3)^4A

35.0 = 491876.5257A

35.0/491876.5257=A

7.1156069x10^-5

is this correct?

Thanks in advance for your help.

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# Homework Help: Boltzman Constant, Emissivity and Surface Area of a filament

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