Q. For comparing the e.m.f.'s of two cells with a potentiometer, a standard cell is used to develop a potential gradient along the wires. Which of the following possibilities would make the experiment unsuccessful
A) The e.m.f. of the standard cell is larger than the $E$ e.m.f.'s the two cells
B) The diameter of the wires is the same and uniform throughout
C) The number of wires is ten
D) The e.m.f. of the standard cell is smaller than the e.m.f.'s of the two cells
Explanation
(d) The emf of the standard cell must be greater than that of experimental cells, otherwise balance point is not obtained
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.