Q. In a typical Wheatstone network, the resistances in cycle order are $A = 10\ \Omega,\ B = 5\ \Omega,\ C = 4\ \Omega$ and $D = 4\ \Omega.$ For the bridge to be balanced
A) $10\ \Omega$ should be connected in parallel with $A$
B) $10\ \Omega$ should be connected in series with $A$
C) $5\ \Omega$ should be connected in series with $B$
D) $5\ \Omega$ should be connected in parallel with $B$
Explanation
(a) For a balance Wheatstone bridge
$\frac{A}{B} = \frac{D}{C} \Rightarrow \frac{10}{5} \neq \frac{4}{4}$ [Unbalanced]
$\frac{A^{'}}{B} = \frac{D}{C} \Rightarrow \frac{A^{'}}{5} = \frac{4}{4} \Rightarrow A^{'} = 5\Omega$
$A'(5\Omega)$ is obtained by connecting a $10\ \Omega$ resistance in parallel with $A$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.