Question

From the following statements:

(A) Neutral temperature is independent of temperature of cold junction.
(B) Peltier effect is the converse of Seebeck effect.

• A. Both A and B are true
• B. Both A and B are false
• C. A is true but B is false
• D. A is false B is true

Answer 1

Answer: (A)

Both A and B are true

In a thermocouple an increase in the hot junction causes an increase in the thermo emf and reaches a maximum value called the neutral temperature(${\theta }_n$). This neutral temperature is independent of
the temperature of the cold junction. For example ${\theta }_n$ for Cu-Fe
thermocouple is ${270}^{\circ }C$.

Peltier Effect is the converse of Seebeck Effect:

Two dissimilar metals when brought in contact with each other produce
a potential difference due to their electron densities. This potential difference is the Peltier emf and denoted by $\pi$. The Peltier emf depends on the temperature of the junction and there is no net emf flows when there exists
a same temperature at the junctions.