Question

When the cold junction of thermo couple is at $0^{0}C$ neutral temperature is ${250}^{0}C$. If the cold junction is at ${10}^{0}C$, neutral temperature is

• A. ${250}^{0}C$
• B. ${240}^{0}C$
• C. ${260}^{0}C$
• D. ${255}^{0}C$

Answer 1

The correct option is A ${250}^{0}C$

The temperature of the hot junction or neutral temperature of a thermo-couple at which the electromotive force of the thermo-couple attains it's maximum value. it does not depend upon the temperature of the cold junction generally temperature of the cold junction is kept at zero degree Celsius but if the cold junction of the thermo-couple is not at $0^{0}C$ but at ${10}^{0}C$,the current will be maximum when the hot junction is at ${250}^{0}C$
so $T_n={250}^{0}C$