Current to heat relation for a wire

AI Thread Summary
The discussion centers on calculating the current capacity of a very small wire, specifically one with a diameter of 100 micrometers and a radius of 1 micrometer. The original poster has attempted to apply the Stefan-Boltzmann law and specific heat capacity but has encountered difficulties due to not accounting for heat loss to the environment and heat sinks. They express a desire to determine the current at which the wire would melt, rather than simply relying on standard gauge tables for current carrying capacity. A question is raised about whether to use resistivity for voltage-current relationships or if additional information from gauge tables is necessary for accurate calculations.
danesh
Messages
6
Reaction score
0
Hey,

I am currently trying to calculate how much current a "wire" of very small dimensions can take. This "wire" is of dimensions of 100 micrometer and radius of about 1 micrometer.
I have tried to use the Stefan-Boltzmann law or use the specific heat capacity, but in there I do not include any lost of heat to the ambient surroundings and to the heat sinks at each end. The results I get are not that good and I feel I have come to a dead end.
I see the connection to filaments in lightbulbs but I haven't been able to find anything in that area.

Anyone who can helps?
 
Physics news on Phys.org
Is there any reason that you are trying to calculate this, rather then simply referring to the gage tables to determine the current carrying capacity of the wire?
 
Sorry for the late reply, no internet connection during weekend.
Well my purpose is to try to calculate when dos the wire melt at different currents.
Do you mean using resistivity to calculate the voltage current relation or is there other information I should look for in the gage tables?
 
Thread 'Motional EMF in Faraday disc, co-rotating magnet axial mean flux'
So here is the motional EMF formula. Now I understand the standard Faraday paradox that an axis symmetric field source (like a speaker motor ring magnet) has a magnetic field that is frame invariant under rotation around axis of symmetry. The field is static whether you rotate the magnet or not. So far so good. What puzzles me is this , there is a term average magnetic flux or "azimuthal mean" , this term describes the average magnetic field through the area swept by the rotating Faraday...
Back
Top