Q. A galvanometer having a resistance of $8\ ohm$ is shunted by a wire of resistance $2\ ohm.$ If the total current is $1\ amp,$ the part of it passing through the shunt will be
A) $0.25\ amp$
B) $0.8\ amp$
C) $0.2\ amp$
D) $0.5\ amp$
Explanation
(b) $i_{g}S = \left( i - i_{g} \right)G \Rightarrow i_{g}(S + G) = iG$
$\Rightarrow \frac{i_{g}}{i} = \frac{G}{S + G} = \frac{8}{2 + 8} = 0.8$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.