QS Study

The voltage sensitivity of a galvanometer is defined as the deflection per unit voltage.

So, Voltage sensitivity = θ/V = θ/IG = nBA/CG

where G is the galvanometer resistance.

An interesting point to note is that, increasing the current sensitivity does not necessarily, increase the voltage sensitivity. When the number of turns (n) is doubled, current sensitivity is also doubled (equation). But increasing the number of turns correspondingly increases the resistance (G). Hence voltage sensitivity remains unchanged.