For the voltmeter circuit shown in the given figure, the

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For the voltmeter circuit shown in the given figure, the basic D’Arsonval meter used has fullscale current of 1 mA and meter resistance (R_m) of 100 ohms. The values of the series resistance R₁ and R₂ required for 10 V range and 50 V range will be respectively

1. 9.9 kΩ and 40 kΩ
2. 10 kΩ and 50 kΩ
3. 20 kΩ and 30 kΩ
4. 200 kΩ and 250 kΩ

Correct Option: A

Full scale meter current = 1 mA

For 10 V range, 10^–3 =	10
	(100 + R₁)

or R₁ = 9.9 × 10³ Ω

For 10 V range, 10^–3 =	50
	(100 + R₁ + R₂)

or R₁ + R₂ = 49.9 × 10³
∴ R₂ = 40 kΩ