Question

What is the condition for using a multiplier in A.C. voltmeters?

(a) by using ac supply

(b) by maintaining a uniform impedance

(c) by maintaining a uniform frequency

(d) by using a galvanometer

This question was addressed to me in an interview.

This intriguing question comes from Shunts and Multipliers in section Extension of Instrument Ranges of Electrical Measurements

Answer 1

The correct answer is (c) by maintaining a uniform frequency

Easy explanation: A multiplier can be used for A.C. voltmeters. The condition to be satisfied is that the total impedance of the voltmeter and the multiplier circuit must be constant for a wide range of frequencies.