Question

A galvanometer has a resistance of 55 ohms. It gives a full scale deflection by a current of 10 m A. What resistance must be connected across it to enable it to read 1 ampere ?
A. `5.55Omega`
B. `0.555Omega`
C. `55.5Omega`
D. `0.055Omega`

Answer 1

Correct Answer - B
`G=55 Omega , I_g = 10m A , I=1A,S=?`
`S=(I_g.G)/(I-I_g)`
`S=(10xx10^-3xx55)/(1-0.010)=0.55Omega` .