# Electric Capacitance And Capacitor - 1

Electric Capacitance And Capacitor

The capacitance of any conductor is its capacity to store charge. As the quantity of charge on conductor is increased its potential also increases. Beyond a limit even if a small additional charge is given then it starts leaking.

Hence Q µ V or Q = CV.

Where C is called capacitance of the conductor. It depends upon geometrical shape and size of the conductor.

If V = 1 volt, then Q = C, hence capacitance of any conductor will be numerically equivalent to that charge which makes its potential equal to 1 volt.

__Unit of capacitance is ‘Farad’: __

1 Farad = 1 coulomb/1 volt.

= coulomb/ (joule/coulomb).

= coulomb^{2}/joule.

= (ampere x second)^{ 2} / ( st1:city st1:placeNewton/st1:place /st1:city x meter).

3) Dimensions of capacitance:

In practice 1 Farad is very large capacity therefore its small units are as following:

1) 1 micro-farad = 10^{-6} farad = 1mf.

2) 1 nano-farad = 10^{-9} farad = 1hf.

3) 1 pico-farad or micro-micro farad = 10^{-12} farad = 1rf = 1mmf.

4)

__Capacitance of spherical conductor: __

For a spherical conductor of radius R,

Potential is

Fig (1)

1) .

2) </span> C µ R.

3) C (capacitance) does not depend upon the charge given.

5) Energy stored in a charged conductor:

6) Redistribution of charge:

Fig (2)