The Wheatstone Bridge was invented in 1833 to measure electrical resistance using a ratio of three known resistors and one unknown resistor. By balancing the bridge, the unknown resistance can be calculated mathematically. It is widely used to this day to monitor sensors and locate breaks in power lines due to its simple, inexpensive, and accurate design.

1. BY:-Ramani Romil
Shoeb Ranger

2.  History
 How does it work?
 How is it used?
 Impact of the circuit
 Summary

3.  The Wheatstone Bridge was invented in 1833
by Samuel Hunter Christie
 Later named after Sir Charles Wheatstone for
his many applications of the circuit through
the 1840s
 The most common procedure for the bridge
remains the testing of unknown electrical
resistance

4.  Uses ratio of 3 known resistors
 Measures fourth unknown resistance
 Balanced voltage between point 1 and
battery’s negative, and between point 2 and
battery’s negative allows the measurement

5.  By changing resistors to adjusting variable
resistors to balance the device, the
mathematical ratio is used to calculate the
fourth (unknown) resistance

7.  Main focus of the Wheatstone Bridge =
applications using electricity
 The circuit monitors sensor devices like strain
gauges – it reads the level of the strain in the
system
 The galvanometer measures whether the
gauges are balanced or not
 Electrical power distributors use the
Wheatstone Bridge to locate breaks in the
power lines

8.  The Wheatstone Bridge is a very simple
design, although there are more complex
versions of achieving the same outcome
 Can be adjusted easily
 Fairly inexpensive to produce
 Also indirectly measures any variable that
would change the resistance of a material
◦ Ex: temperature, force, pressure

9.  Created in 1833, popularized in 1840s
 Wheatstone bridges are one of the best methods of
measuring resistance due to the basic mathematical
ratio involved.
 Accurate standards with sensitive enough voltmeter,
measurements of resistance within .05% can be reached.
 Many calibration laboratories still use this method
today.
 The Wheatstone Bridge are replaceable; however, for its
simplicity and versatility the circuit is an indispensible
piece of technology