(3.5) |
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units: ohms . m |
The power density based on Ohm's law is | ||
(3.6) |
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units: ohms . m |
where Ac = cross-sectional area of the rod (m2) and is given in (3.5). | ||
Substituting from (3.5) and (3.6) into (3.1), we get the differential equation | ||
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which can be simplified to | ||
(3.7) |
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where | ||
(3.8) |
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(3.9) |
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to obtain the temperature distribution in the rod.