What is thermo e.m.f. ?? Explain its origin in a THERMOCOUPLE ..........?

Question

ALSO EXPLAIN ITS VARIATION WITH TEMPERATURE

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Answer 1

The e.m.f. set up in a thermocouple , when its two juncions are kept at different temperatures is called thermo e.m.f. .

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Answer 2

Thermo EMF is the effect that appears when you have 2 wires made of different materials connected. The junctions made y the connections are then exposed to different temperatures.

What happens is tht the temperature difference between juctions causes a different effect on each material. Each wire releases a certain amount of electrons near the juction. There is a different amount of electrons per wire. The individual reactions to the wires create a potential difference (and current) between the wires, which can be measured across one of the wires.

The higher the temperature difference, the bigger is the difference in the wires. So more EMF.

Answer 3

thermocouple is basically a transducer which converts physical quantity (temp) into equivalent electrical signal
principle : when 2 dissimilar metal wires r joint together so as to form to junctions & if one junction is heated while other is keppt at reference temp than a smll current in mA is measured across the to wires which is called as THERMO emf

Answer 4

What Is Meant By Thermocouple