When a galvanometer is connected to the shunt resistance, then we have potential drop across the galvanometer = potential drop across the shunt i.e. iG=(i0−i)S ...(i) Here, i= current through the galvanometer G= resistance of the galvanometer i0= current through the shunt resistance S= shunt resistance From Eq. (i), we have the part of the total current that flows through the galvanometer is