A galvanometer of resistance 5 ohms gives a full scale deflection for a potential difference of 10 mV. To convert the galvanometer into a voltmeter giving a full scale deflection for a potential difference of IV. the size of the resistance that must be attached to the voltmeter is

Question

A galvanometer of resistance 5 ohms gives a full scale deflection for a potential difference of 10 mV. To convert the galvanometer into a voltmeter giving a full scale deflection for a potential difference of IV. the size of the resistance that must be attached to the voltmeter is (A) 0.495 ohm (B) 49.5 ohm (C) 495 ohm (D) 4950

Tardigrade Admin · Accepted Answer

I g =10 × 10-3 / 5=2 × 10-3 A R =( V / I g )- R g =(1/2 × 10-3)-5=495 Ω

Q. A galvanometer of resistance $5$ ohms gives a full scale deflection for a potential difference of $10 mV$ . To convert the galvanometer into a voltmeter giving a full scale deflection for a potential difference of $I V$ . the size of the resistance that must be attached to the voltmeter is

0.495 ohm

49.5 ohm

495 ohm

4950

$I_{g} = 10 \times 1 0^{- 3} /5 = 2 \times 1 0^{- 3} A$
$R = \frac{V}{I _{g}} - R_{g} = \frac{1}{2 \times 1 0 ^{- 3}} - 5 = 495 Ω$

Q. A galvanometer of resistance 5 ohms gives a full scale deflection for a potential difference of 10mV. To convert the galvanometer into a voltmeter giving a full scale deflection for a potential difference of IV. the size of the resistance that must be attached to the voltmeter is