Physics: Wheatstone bridge

Keywords: physics, Wheatstone bridge, unknown resistance


A Wheatstone bridge is a device which is used to find the unknown resistance.1,3 It is an instrument or a circuit consisting of four resistors or their equivalent in series which is used to determine the value of an unknown resistance when the other three resistances are known.1-4 One is variable resistance, which is also called the rheostat of the circuit, and two known resistances. It also contains the galvanometer for the detection of the current and it is also used to find the direction of current.

Author Biography

R Lockhat, University of the Witwatersrand

Department of Anaesthesia, Charlotte Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, South Africa

FCA 1 Anaesthetic Refresher Course 2020