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Calculate the value of the multiplier resistors R₁ to R4 in the design of a multi-range voltmeter with voltage ranges of 0-10 V, 0 - 40 V, 0-75 V, and 0-200 V. Draw also the circuit diagram and label them properly. Rm = 2k ohms IFSD = 60 μA

four voltage ranges are given

Rm = internal resistance of voltmeter = 2k

let Im= full scale deflection current of meter=60 microA

Let us consider the voltmeter of voltage range 0-10 V

Here let full range voltage of instrument V 1=10 V

Let voltage across the meter movement for current Im = v

since current through the meter having resistance Rm is Im

R1 = multiplier resistance in the first case

since Rm and R1 are connected in series and current flowing is Im and full range voltage is V1

we know multiplying factor m= V/v

putting the values of V and v, Rn is multiplier resistance