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)

Which among the following options needs to be decreased to increase the sensitivity of a moving coil galvanometer?

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. $i\propto \sqrt{\theta }$ 

The current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit voltage applied) is 20 div/V. How much is the resistance of the galvanometer?

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

What is the relation between voltage sensitivity (σ_v) and current sensitivity (σ_i) of a moving coil galvanometer? (Resistance of Galvanometer = G)

1. $\frac{{\sigma }_i}{G}={\sigma }_v$                           

2. $\frac{{\sigma }_v}{G}={\sigma }_i$

3. $\frac{G}{{\sigma }_v}={\sigma }_i$                           

4. $\frac{G}{{\sigma }_i}={\sigma }_v$