How Do You Calculate the Length of a Wire in a 60W Incandescent Bulb?

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To calculate the length of the wire in a 60W incandescent bulb, the resistivity is crucial but not provided, leading to confusion about which equations to use. The relationship between resistivity, resistance, area, and length is highlighted, but two variables are missing, complicating the calculation. The discussion suggests considering the wire as a blackbody radiator, which may relate to the Stefan-Boltzmann equation. This approach could help in deriving the necessary parameters for the calculation. Understanding these concepts is essential for accurately determining the wire length in the bulb.
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Homework Statement
Finding the length of a wire of incandescent light bulb.
Relevant Equations
N/A
How to find the length of a wire of a 3000 Kelvin incandescent light bulb that produces L = 60W of power. The diameter of the wire is 0.00005m.

I'm quite confused, as the resistivity of the bulb isn't given so I'm not sure what equation to use as resistivity = resistance × area / length does not seem to work because I'm missing 2 variables.
 
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UnknownSoldier02 said:
Homework Statement: Finding the length of a wire of incandescent light bulb.
Homework Equations: N/A

How to find the length of a wire of a 3000 Kelvin incandescent light bulb that produces L = 60W of power. The diameter of the wire is 0.00005m.

I'm quite confused, as the resistivity of the bulb isn't given so I'm not sure what equation to use as resistivity = resistance × area / length does not seem to work because I'm missing 2 variables.
Think of the wire as a blackbody radiator.
 
tnich said:
Think of the wire as a blackbody radiator.
Would it be related to the Stefan-Boltzmann equation in some way?
 
UnknownSoldier02 said:
Would it be related to the Stefan-Boltzmann equation in some way?
Yes.
 

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