A galvanometer coil has a resistance of 10 $\Omega$ and the meter shows full scale deflection for a current of 3.0 mA. To convert it into a voltmeter of range 15 V a resistor R
Answer & explanation
Correct answer: option 3
The reading of voltmeter to become 15V.
A large Resistance of Rs should be connected in series.
$\Rightarrow I(R+R_s) = V $
$ R_s = \frac{V}{I} - R = \frac{15}{3\times10^{-3}} - 10 = 4990\Omega$