The
thermoelectric effect is the
voltage created from one end of a conductor to the other when one end is a different
temperature then the other. The reverse is also possible, whereby a voltage across two different materials creates a difference in temperature. This is the
Peltier effect.
Electrons flow from the hot end to the cold end.
Different materials will create different voltage potentials.
Thus, a thermocouple works by measuring the difference in potential caused by the dissimilar wires.
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