Question

The resistance of a moving coil galvanometer is $20\Omega .$ It requires $0.01A$ current for full scale deflection. Calculate the value of resistance required to convert it into a voltmeter of range $20$ volt:-

• A. $1980\Omega$
• B. $2000\Omega$
• C. $1880\Omega$
• D. $1500\Omega$

Answer 1

Answer: (A)

$V=i\left(R+S\right)$
$20=\left(0.01\right)\left(20+S\right)$
$\rho =1980\Omega$