A galvanometer of 50 ohm resistance has 25 divisions. A current 4 10⁻⁴ ampere gives a deflection of one division. To convert this galvanometer into a voltmeter having a range of 25 volts, it should be connected with a resistance of:

Step-by-step solution

Total current in the galvanometer = aligned & 25 4 10⁻⁴ ~A & I _g=10⁻² ~A aligned The value of resistance connected in series to convert galvanometer into voltmeter of 25 ~V is aligned R & = V I_g -G & = 25 10⁻² -50 & =2450 aligned