Q. A thermocouple is formed by two metals $X$ and $Y,$ metal $X$ comes earlier to $Y$ in Seebeck series. If temperature of hot junction increases beyond the temperature of inversion, then direction of current in thermocouple will be from
A) $X$ to $Y$ through cold junction
B) $X$ to $Y$ through hot junction
C) $Y$ to $X$ through cold junction
D) Both (b) and (c)
Explanation
(d) In the normal condition current flows from $X$ to $Y$ through cold junction. After increasing the temperature of hot junction beyond temperature of inversion the current is reversed $i.e.\ X$ to $Y$ through hot junction or $Y$ to $X$ through cold junction
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.