A cold-water pipe and a hot-water pipe are both made of copper and are initially electrically isolated. In which one of the following arrangements will the galvanometer indicate a thermo-electric current?

Question

Dr. Abubacker · Accepted Answer

(d) The thermo-couple works in a closed circuit. Since the two pipes are isolated, only $b\ and\ a$ are closed-circuits.
In circuit $b$, the two constantans wires to the cold copper
pipe produce 2 opposing currents.
In circuit $a$, the copper-constantan junction is maintained across the cold pipe. A steady current can flow.

Q. A cold-water pipe and a hot-water pipe are both made of copper and are initially electrically isolated. In which one of the following arrangements will the galvanometer indicate a thermo-electric current?

Explanation

Reviewed by Dr. Abubacker

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