A galvanometer having a resistance of \( 7\,\Omega \) is shunted by a resistance of \( 3\,\Omega \). If the total current is 1 A, the value of current passing through the shunt is
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 0.7 A
A shunt is in parallel with the galvanometer, so the two branches have the same potential difference and the current divides in the inverse ratio of the resistances.
\( \displaystyle I_{S} = I\,\frac{G}{G + S} = 1 \times \frac{7}{7 + 3} = 0.7\,\mathrm{A} \)
The galvanometer itself carries \( 1 - 0.7 = 0.3\,\mathrm{A} \).