Wheatstone bridge

Wheatstone bridge is a measuring instrument invented by Samuel Hunter Christie in 1833 and improved and popularized by Sir Charles Wheatstone in 1843. This is used to measure an unknown electrical resistance by balancing two legs of the bridge, one leg that includes the components known. it works similar to the original potentiometer.

Basic law of electric circuits associated with the Wheatstone bridge:

1. Ohm's Law
Ohm's Law states "If an electric current through a conductive, the current strength is proportional to the voltage-larus contained between the two ends of Conductor earlier."

This law was coined by Georg Simon Ohm, a physicist from Germany in 1825 and published in a paper entitled The Galvanic Circuit Investigated Mathematically in 1827.


The formula for Ohm's Law

Mathematically, Ohm's law is written

V = I.R
or
I = V / R

where
I = electric current that flows in a Conductor (Ampere)
V = voltage found on both ends of the Conductor (Volt)
R = electrical resistance found in a Conductor (Ohm)

2. Kirchoff Law I
Mid-19th century, Gustav Robert Kichoff (1824-1887) found a way to determine the electric current in the circuit branch which became known to the law of Kirchoff. Kirchoff law reads "The number of strong currents that enter the branching point equal to the amount of flow coming out strong from the point of branching."

The number I enter = I out

3. Kirchoff Law II
Kirchoff Law II reads, "In a closed circuit, the algebraic sum emf (E) and total potential drop equal to zero."

Purpose of the total potential drop equal to zero is the absence of electrical energy is lost in the circuit or in the sense that all energy can be used or absorbed.