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Finding the Length of a wire

  • #1

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.
 

Answers and Replies

  • #2
tnich
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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.
 
  • #3
Think of the wire as a blackbody radiator.

Would it be related to the Stefan-Boltzmann equation in some way?
 
  • #4
haruspex
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