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For a thermocouple, the emf is expressed as E = αT + (1/2)βT², where T denotes the temperature of the hot junction and the cold junction is maintained at 0°C. The thermoelectric power of the couple is:

1. α + βT/2
2. α + βT
3. αT²/2 + βT³/6
4. α/(2β)

Correct answer: α + βT

Solution

Thermoelectric power is dE/dT. With E = alpha*T + (1/2)*beta*T^2, dE/dT = alpha + beta*T.

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