Calculating Delta T for a Resistor - Philip's Guide

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To calculate the change in temperature (Delta T) for a resistor, additional information is needed, specifically the resistivity of the material or the potential gradient producing the current density. Without this data, it's impossible to determine the Ohmic power loss, which is essential for calculating temperature change. The discussion highlights that the provided parameters alone—specific heat, density, current density, and time—are insufficient for solving the problem. Philip acknowledges that his professor likely omitted the necessary resistivity information from the problem statement. Accurate calculations depend on having all relevant variables included.
philipc
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Lets say I'm given a 'specific heat, density, currenty density J, and the time that J exist, how can if find the the change in Temperature? My main problem is I don't know how to start the problem, a couple pointer in the right direction would be great.
Thanks
Philip
 
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philipc said:
Lets say I'm given a 'specific heat, density, currenty density J, and the time that J exist, how can if find the the change in Temperature? My main problem is I don't know how to start the problem, a couple pointer in the right direction would be great.
Thanks
Philip

I don't think you have enough information here to solve this. You need at least one more info, either the potential gradient that is producing that current density, or the resistivity of the material (these two values are related). This is because, for the SAME current density, materials with different resistivity will produce different Ohmic power loss - this is what needs to be used to find the change in temperature.

Zz.
 
Zz,
thanks for your quick response
I just read the question again and I guess my professor forgot to put resistivity into the problem, but the final answer does include it.
Philip
 

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