Question

For comparing the electromotive force of two cells with a potentiometer, a standard cell is used to develop a potential gradient along the wire. Which of the following possibilities would make the experiment unsuccessful?

• A. The electromotive force system of the standard cell is larger than the $E$ electromotive force system of the two cells.
• B. The diameter of the wires is the same and uniform throughout
• C. The number of wires is ten
• D. The electromotive force of the standard cell is smaller than the electromotive force of the two cells.

Answer 1

Answer: (D)

The electromotive force of the standard cell is smaller than the electromotive force of the two cells.

The emf of the cell standard cell must be greater than that of experiment cells, otherwise balance point is not obtained.