Question

emf of any cell can be measure by

Select one:

a. wheatstone bridge

b. potentiometer

c. ammeter

d. voltmeter

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Answer 1

Answer:

The potentiometer is the right answer. Electromotive force is measured using potentiometers.

Explanation:

• By finding the balance length, we may use a potentiometer to calculate the EMF of a cell (l). Since no current is being pulled from the cell, the fall in potential along the length l of the wire is equal to the emf of the cell.
• Since the potentiometer is a null device and does not draw any current, it is preferable over the voltmeter when measuring the emf of the cell. Voltmeter, however, uses the cell's current.
• See if E1 > E and E2 > E by measuring the EMF (E) of the battery and the EMFs (E1 and E2) of the cell. Connect the battery's positive pole to one of the potentiometer's zero ends (P) and its negative pole through a one-way key, a low resistance rheostat, and an ammeter to the opposite end (Q).