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Laboratory work #34
THE DETERMINATION OF THE CAPACITANCE OF
CONDENSER BY SAUTY BRIDGE

Aim of work: to determine unknown capacitance of given
condensers.
Laboratory equipment: the Sauty Bridge, a set of unknown

condensers, a standard capacitor.
1. The Capacitance
Any two conductors separated by an insulator are said to form a
capacitor or condenser. In most cases of practical interest the

conductors usually have charges of equal magnitude and opposite sign,
so the net charge on the capacitor on the whole is zero. The electric
field in the area between the conductors is then proportional to the

magnitude of this charge, and it follows that the potential difference
V between the conductors is also proportional to the charge magnitude
q.

The capacitance C of a capacitor is defined as the ratio of the
magnitude of the charge q on either conductor to the magnitude of the

potential difference V between the conductors:
q
C  (1.1)
V
As it follows from the formula (1) the unit of capacitance is one

C
coulomb per volt ( ). A capacitance of one coulomb per volt is
V
called one farad (1 F).

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