Q. A potentiometer circuit shown in the figure is set up to measure e.m.f. of a cell $E.$ As the point $P$ moves from $X$ to $Y$ the galvanometer $G$ shows deflection always in one direction, but the deflection decreases continuously until $Y$ is reached. In order to obtain balance point between $X$ and $Y$ it is necessary to
A) Decreases the resistance $R$
B) Increase the resistance $R$
C) Reverse the terminals of battery $V$
D) Reverse the terminals of cell $E$
Explanation
The correct answer is Option A: Decreases the resistance $R$.
A detailed explanation for this question is being prepared.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.