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A thermocouple is made from two metals, ...

A thermocouple is made from two metals, Antimony and Bismuth. If one junction of the couple is kept hot and the other is kept cold, then, an electric current will

A

flow from antimony to bismuth at the cold junctions

B

flow from antimony to bismuth at the hot junctions

C

flow from bismuth to antimony at the cold junction

D

not flow through the thermocouple

Text Solution

Verified by Experts

The correct Answer is:
A
When a circuit is made up of any two metals in thermoelectric series, the current flows across the cold junction from the later occuring metal in the series to the one the one occuring earlier. In thermoelectric series Bismuth comes earlier than Antimony. so, at cold junction current flows from Antimoty Bismuth and at hot junction it flows from Bismuth to Antimony.
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