![A moving coil instrument having a resistance of 10 Ω, gives a full-scale deflection when the current is 10 mA](https://www.gkseries.com/blog/wp-content/uploads/2023/08/A-moving-coil-instrument-having-a-resistance-of-10-Ω-gives-a-full-scale-deflection-when-the-current-is-10-mA.jpg)
Q. A moving coil instrument having a resistance of 10 Ω, gives a full-scale deflection when the current is 10 mA. What should be the value of the series resistance, so that it can be used as a voltmeter for measuring potential difference up to 100 V?
(A) 9 Ω
(B) 99 Ω
(C) 990 Ω
(D) 9990 Ω
Ans: 9990 Ω
Solution:
![](https://www.gkseries.com/blog/wp-content/uploads/2023/08/Screenshot-551.png)