A network consists of four resistors connected between four junctions A, B, C and D…
PHYSICS · Multi-part · CBSE · Physics · Current Electricity · Current Electricity
Problem
A network consists of four resistors connected between four junctions A, B, C and D such that AB and AD form one pair of opposite arms while BC and DC form the other pair. A sensitive galvanometer of negligible internal resistance is connected between B and D and a steady d.c. source is connected between A and C.
(i) Define the term “balanced bridge” for this arrangement.
(ii) Explain, with reference to potential differences at the points B and D, why the galvanometer shows zero deflection when the bridge is balanced even though a finite current is drawn from the source.
(iii) State any two practical advantages of operating a bridge circuit under balance.