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CBSE Class 12 · 2003 · Current ElectricityVery Short Answer

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Name the temperature for a thermocouple at which its
(i) thermo-emf changes its sign, and
(ii) thermoelectric power becomes zero.

Solution

For a thermocouple the thermo-emf rises with the temperature of the hot junction up to the \emph{neutral temperature} (where , i.e. thermoelectric power is zero), then falls, becoming zero and reversing sign at the \emph{temperature of inversion} .

CBSE Class 12 Board · 2003 · Subjective

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