Capacitor Tutorial Summary





	
 Capacitor Tutorial Summary


A capacitor consists of two metal plates separated by a dielectric


As we will see in this capacitor tutorial, Capacitors are energy storage
devices which have the ability to store an electrical charge across its
plates. Thus capacitors store energy as a result of their ability to store
charge and an ideal capacitor would not loose its stored energy.

The simplest construction of a capacitor is by using two parallel conducting
metal plates separated through a distance by an insulating material. This
insulating material is called the “dielectric”. the dielectric plays an
important role in the electrical operation of a capacitor and for this
capacitor tutorial we can summarise the main points below.

A capacitor consists of two metal plates separated by a dielectric.
The dielectric can be made of many insulating materials such as air,
glass, paper, plastic etc.
A capacitor is capable of storing electrical charge and energy.
The higher the value of capacitance, the more charge the capacitor can
store.
The larger the area of the plates or the smaller their separation the
more charge the capacitor can store.
A capacitor is said to be “Fully Charged” when the voltage across
its plates equals the supply voltage.
The symbol for electrical charge is Q and its unit is the Coulomb.
Electrolytic capacitors are polarized. They have a +ve and a -ve
terminal.
Capacitance is measured in Farads, which is a very large unit so micro
-Farad ( μF ), nano-Farad ( nF ) and pico-Farad ( pF ) are generally used.
Capacitors that are daisy chained together in a line are said to be
connected in Series.
Capacitors that have both of their respective terminals connected to
each terminal of another capacitor are said to be connected in Parallel.
Parallel connected capacitors have a common supply voltage across them.
Series connected capacitors have a common current flowing through them.
Capacitive reactance, XC is the opposition to current flow in AC
circuits.
In AC capacitive circuits the voltage “lags” the current by 90o.

The basic construction and symbol for a parallel plate capacitor is given
as:
	
	capacitor tutorial the symbol