Question

The scale of galvanometer of resistance 100 ohm contains 25 divisions .It gives a deflection of 1 division when 4 a current is passed through it .The resistance in ohms is connected in series to it .So that it becomes a volt meter of range 2.5 volt is

Answer 1

Answer:

150

Explanation:

Given The scale of galvanometer of resistance 100 ohm contains 25 divisions .It gives a deflection of 1 division when 4 x 10^-4 a current is passed through it .The resistance in ohms is connected in series to it .So that it becomes a volt meter of range 2.5 volt is

Given resistance of galvanometer G = 100 ohm, Number of divisions is 25, current I = 4 x 10^-4 amps, given ig = 4 x 25 x 10^-4 = 10^2 x 10^-4 = 10^-2 amps, V = 2.5 v  

To convert galvanometer to voltmeter

Now shunt resistance R = V / ig – G

                                   R = 2.5 / 10^-2 – 100

                                  R = 2.5 x 10^2 – 100

                                 R = 250 – 100

                                R = 150 ohms