Question 241:
easyA galvanometer of $50\text{ }\Omega$ resistance has $25$ divisions. A current of $4 \times 10^{-4}\text{ A}$ gives a deflection of one division. To convert this galvanometer into a voltmeter having a range of $25\text{ V}$, it should be connected with a resistance of: (2004)
Full scale current $I_g = 25 \times 4 \times 10^{-4} = 0.01\text{ A}$. Required series resistance $R = \frac{V}{I_g} - G = \frac{25}{0.01} - 50 = 2450\text{ }\Omega$.