Example A shunt type ohmmeter uses a $10$ mA basic d'Arsonval movement with an internal resistance of $\backslash (5\backslash$Omega $\backslash ).$ The battery emf is $3$ V $.$ It is desired to modify the circuit by adding appropriaie shunt resistances across the movement so that its instrument indicates $\backslash (0\mathrm{.}5\backslash$Omega $\backslash )$ at the mid$-$point on its scale.

Calculate $($a$)$ the value of shunt resistance

$($b$)$ Value of current limiting resistor $\backslash ($ R$\_\{1\}\backslash )$

Ohmmeter $($Shunt$)$