Question

why thermal conductivity decreases when the temperature difference increases

why thermal conductivity decreases when the temperature difference increases

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Answer #1

Ans :

The thermal conductivity of substances is dependent on various factors such as : chemical composition , phase change , temperature etc.

When the temperature of a metal is increased , the mean free path of the molecules decreases. The thermal conductivity directly relates with the mean free path and absolute temperature.

This causes a decrease in the conduction of heat , so the the thermal conductivity decreases when the temperature difference increases.

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