Wheatstone Bridge:

The Wheatstone Bridge is an electrical circuit used to measure an unknown resistance by balancing two legs of a bridge circuit. It was invented by Samuel Hunter Christie in 1833 and popularized by Sir Charles Wheatstone in 1843. The bridge consists of four resistors connected in a diamond-shaped configuration, with a voltage source applied across the circuit and a galvanometer to detect current flow.

Why Do We Use the Wheatstone Bridge?

To Measure Unknown Resistance: It is primarily used to determine the value of an unknown resistance with high precision by comparing it to known resistances.
High Accuracy: The bridge provides more accurate results than direct measurements with an ohmmeter because it eliminates errors caused by variations in voltage and current.

Wheatstone Bridge Formulas:

R1 = (R2 × R3) / R4

R2 = (R1 × R4) / R3

R3 = (R1 × R4) / R2

R4 = (R2 × R3) / R1

Rasistance Calculation:

Formula for R1:

R1 = (R2 × R3) / R4 = (20 × 30) / 40 = 15

Formula for R2:

R2 = (R1 × R4) / R3 = (15 × 40) / 30 = 20

Formula for R3:

R3 = (R1 × R4) / R2 = (15 × 40) / 20 = 30

Formula for R4:

R4 = (R2 × R3) / R1 = (20 × 30) / 15 = 40

Wheatstone Bridge Circuit