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

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Homework Help Overview

The discussion revolves around calculating the length of a wire in a 60W incandescent bulb, specifically considering the wire's properties and the bulb's operating temperature of 3000 Kelvin.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants express confusion regarding the missing resistivity value and its impact on using the resistivity formula. There is a suggestion to consider the wire as a blackbody radiator, leading to questions about the relevance of the Stefan-Boltzmann equation.

Discussion Status

Participants are exploring the relationship between the wire's properties and thermal radiation concepts. Some guidance has been offered regarding the blackbody radiator perspective, but no consensus has been reached on the approach to take.

Contextual Notes

The discussion highlights the lack of specific information, such as the resistivity of the wire, which is critical for applying relevant equations. Participants are navigating through assumptions related to the physical properties of the wire and 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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