Question

For thermo couple at neutral temperature
Statement A : Thermo emf is maximum
Statement B : Thermoelectric Power is zero.
In these statements,

• A. A is correct, B is wrong
• B. A is wrong, B is correct
• C. Both A and B are correct
• D. Both A and B are wrong

Answer 1

The correct option is C Both A and B are correct

In a thermocouple as the temperature of the hot junction is increased with the cold junction at a fixed temperature, the thermo emf increases until a maximum temperature called the neutral temperature. At the neutral temperature, thermo emf is maximum.

Thermoelectric power is defined as the rate of change of thermoelectric emf with temperature and is also known as Seebeck coefficient. The thermoelectric power is determined by the slope of the thermo electric curve. The slope at the neutral temperature is zero and hence thermo electric power is zero.