Why potentiometer is not used to measure ac current

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Solution

Dear Student

The Potentiometer used to compare the two different emf of battery and potentiometer is an instrument for variable voltage in a circuit. Before the introduction of the moving coil and digital volt meters, potentiometer were used in measuring voltage. The method was described by Johann Christian Pogendorff around 1841 and became a standard laboratory measuring technique.

The AC changes the direction continuously, so its impossible to measure on the galvanometer as well as to compare the emf of two sources.

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