Electric circuits: elements and representation
An electric circuit is a route around which electrons circulate.
It consists of a generator, a cable, a switch and a receiver.
Electric current is the flow of electrons around a circuit
We need a generator in to maintain a current.
There are three types of materials.Conductors,Insulators,semiconductors:
Conductors allow electric current to pass through them. All metals are conductors
Insulators don’t allow an electric current to pass through them wood glass, plastic and the air are insulators
Semiconductors have properties which are intermediate in magnitude between conductors and insulators. The most important examples are silicon and germanium.
The electric resistance of the material is the measure of the degree to which the material opposes an electric current flowing through it
Metals have hardly any electrical resistance whereas insulators have a very high level of resistance
Its value depends on the material used and its form.
Resistance increases with the length of the cable and decreases with its thickness
Elements of a circuit
The generator provides the necessary energy for electrons to circulate
The control elements direct and interrupt electric current
The receivers transform electric energy into usable energy
The protection elements protect circuits and people against potential problems