Q. The rate of increase of thermo e.m.f. with temperature at the neutral temperature of a thermocouple
A) Is negative
B) Is positive
C) Is zero
D) Depends upon the choice of the two materials of the thermocouple
Explanation
[Solution from source] Thermo emf rises with temperature, reaches a maximum at the neutral temperature, and then falls. At a maximum the slope dE/dθ is zero. It does not depend on the materials at that point, although the neutral temperature itself does. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.