When will the current sensitivity of a moving coil galvanometer be high?
(N = number of turns, B = magnetic field, A = area of coil, and C = Torsional constant of spring)

By which relation is the deflection of the coil θ related to the electrical current i in a moving coil galvanometer?

1. $i\propto \tan \theta$                 

2. $i\propto \theta$ 

3. $i\propto {\theta }^2$                    

4. $i\propto \sqrt{\theta }$ 

What happens when the number of turns in a galvanometer is doubled?