Wheatstone's Bridge MCQ - Practice Questions with Answers

Wheatstone's Bridge

It is an arrangement of four resistances which can be used to measure one of them in terms of rest. Let R is an adjustable resistance, Pand Q are known resistance and S is an unknown resistance. To obtain valur of S we will close the keys K1 and K2 and will adjust R to obtain null deflection in the galvanometer. Then the balancing condition of bridge is 

$\begin{array}{rl}& \frac{P}{Q}=\frac{R}{S}\\ & V_B=V_D\end{array}$

(Balanced condition )
No current will flow through the galvanometer unbalanced condition: $V_B>V_D$

$(V_A-V_B)<(V_A-V_D)$

Current will flow from $A$ to $B$