Question

If the cold junction of a thermocouple is kept at $0^{\circ }C$ and the hot junction is kept at $T^{\circ }C$, then the relation between neutral temperature $\left(T_n\right)$ and temperature of inversion $\left(T_i\right)$ is

• A. $T_n=\frac{T_i}{2}$
• B. $T_n=2T_i$
• C. $T_n=T_i-T$
• D. $T_n=T_i+T$

Answer 1

Answer: (A)

We know temperature of inversion $\left(T_i\right)$ is as much above the neutral temperature $\left(T_n\right)$ as neutral temperature is above the temperature of the cold junction $(T)$,
i.e., $T_i-T_n=T_n-T$ or $T_i=2T_n-T$
But, here the cold junction is kept at $0^{\circ }C$, hence $T=0$
Thus, $T_i=2T_n$ or $T_n=\frac{T_i}{2}$