A galvanometer with a coil resistance of 50 requires a shunt resistance of 0.5 to function as an ammeter that can read currents up to 1.01 ~A . The value of the series resistance required to convert this same galvanometer into a voltmeter that can read up to 5 ~V is :

Step-by-step solution

Let the full-scale deflection current of the galvanometer be I _ g . For the ammeter conversion: I _ g R _ g = ( I - I _ g ) S I _ g 50 = (1.01 - I _ g ) 0.5 50 I _ g = 0.505 - 0.5 I _ g 50.5 I _ g = 0.505 I _ g = 0.01 ~A For the voltmeter conversion: V = I _ g ( R _ g + R _ s ) 5 = 0.01 (50 + R _ s ) 500 = 50 + R _ s R _ s = 450 Answer: 450