The resistance of a moving coil galvanometer is 20 Ω . It requires 0.01A current for full-scale deflection. The value of resistance to convert it into a voltmeter of the range 20 V will be

Question

The resistance of a moving coil galvanometer is 20 Ω . It requires 0.01A current for full-scale deflection. The value of resistance to convert it into a voltmeter of the range 20 V will be (A) 198 Ω (B) 1980 Ω (C) 20 Ω (D) 0 Ω

Tardigrade Admin · Accepted Answer

VG=IGG VG=0.01× 20=0.2 V R=((V/VG) - 1)G R=((20/0.2) - 1)(20)=1980 Ω

Q. The resistance of a moving coil galvanometer is $20 Ω$ . It requires $0.01 A$ current for full-scale deflection. The value of resistance to convert it into a voltmeter of the range $20 V$ will be

$198 Ω$

$1980 Ω$

$20 Ω$

$0 Ω$

$V_{G} = I_{G} G$
$V_{G} = 0.01 \times 20 = 0.2 V$
$R = (\frac{V}{V _{G}} - 1) G$
$R = (\frac{20}{0.2} - 1) (20) = 1980 Ω$

Q. The resistance of a moving coil galvanometer is 20Ω . It requires 0.01A current for full-scale deflection. The value of resistance to convert it into a voltmeter of the range 20V will be

198Ω

1980Ω

20Ω

0Ω