Question

A moving coil galvanometer of $50\Omega$ resistance gives full deflection when a current of $0.5\text{mA}.$ To convert this galvanometer into a voltmeter of $10\text{V}$ range, the resistance to be connected in series with the galvanometer is

• A. $18005\Omega$
• B. $20050\Omega$
• C. $19050\Omega$
• D. $17050\Omega$

Answer 1

The correct option is C $19050\Omega$

Given, $G=50\Omega ;I_g=0.5\text{mA};V=10\text{V}$

$V=I_g(G+R)$

$10=0.5\times {10}^{-3}(50+R)$

$2\times {10}^4=50+R$

$R=20000-50$

$R=19050\Omega$

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Hence, $\left(C\right)$ is the correct answer.