Two cells of emfs approximately 5 V and 10 V are to be accurately compared using a potentiometer of length 400 cm .
A
The battery that runs the potentiometer should have voltage of 8 V
B
The battery of potentiometer can have a voltage of 15 V and 
adjusted, so that the potential drop across the wire slightly exceeds 10 V
adjusted, so that the potential drop across the wire slightly exceeds 10 V C
The first portion of 50 cm of wire itself should have a potential drop of 10 V
D
Potentiometer is usually used for comparing resistances and not voltages
Text Solution
Verified by ExpertsThe correct answer is:
B
In potentiometer experiment, the emf of a cell can be measured, if the potential drop along the potentiometer wire is more than the emf of the cell to be determined. Here, value of emfs of two cells are given as 5 V and 10 V, therefore the potential drop along the potentiometer wire must be more than 10 V.
Prepare Smarter with CGP Edu
Get practice questions, solutions, and test series in one place.
Write a Review
Share your experience with this question and solution.
Commentary
Send your comment, doubt, correction, or feedback to admin.
Similar Questions
Explore conceptually related problems
Two cylindrical rods of uniform cross-section area A and 2 A, having free electrons per unit volume…
A copper wire is connected across an ideal battery. The drift velocity of the electrons is v. If an…
The dimensional formula of mobility is
A current flows in a wire of circular cross-section with the free electrons travelling with a mean …
A wire has a non-uniform cross-sectional area, as shown in the figure. A steady current i flows thr…
A uniform copper wire carries a current i amperes and has q charge carriers percubic meter. The len…