A galvanometer has a resistance of 50 Ω and it allows maximum current of 5 mA . It can be converted into voltmeter to measure upto 100 V by connecting in series a resistor of resistance.

Step-by-step solution

If we connect a high resistance( R ) in series with the galvanometer, it can be successfully converted into a voltmeter. Therefore, Voltage drop across voltmeter: V = I g R g + R ⇒ 100 = I g 50 + R ⇒ R = 100 5 × 10 - 3 - 50 = 19950 Ω