Question

Explain about wheatstone bridge

Answer 1

Hi there!

WHEAT STONE BRIDGE: It is an arrangement of four resistance connected to form the arms of quadrilateral ABCD.
A battery with key and galvanometer are connected along its two diagonals respectively.

As in the given attachment,
• P,Q = ratio arms,
• R = known resistance,
• S = unknown resistance

The bridge is said to be balanced when :
(1) VB = VD

(2) There is no flow of current through galvanometer.

The Wheatstone bridge is said to be sensitive, if it gives ample deflection in the galvanometer even on slight change of resistance.
For sensitivity of galvanometer, the magnitude of four resistances P, Q, R, S should be of same order.

HOPE IT HELPS!!