Basic Electrical Symbols


Electric circuits, can be described in a variety of ways. A visual way to describe an electrical circuit should be to draw it as a diagram using basic electrical symbols. So let’s learn about these symbols.

Basic Electrical Symbols

Basic electrical symbols like earth, electrode, cell, battery, source, ideal source are included here.


Heating effect of electricity

A metallic conductor like an electric wire has free electrons. When a potential difference is applied across the ends of a metallic wire; the free electrons begin to move from the low potential to the high potential region. These moving electrons hit the positive ions. The energy of the electrons is transferred to the positive ions and they begin to vibrate more violently. As a result, heat is produced.

Application of the heating effect of current

Electrical heating appliances such as electric iron, room heaters, water heaters use the heating effect of current. All these heating appliances contain coils of high resistance wire made of alloys such as nichrome. When these appliances are connected to a power supply then a large amount of heat is produced in the heating coils because they have high resistance. But, a negligible heat is produced in the connecting wires because the wires are made to have low resistance.


The heating effect of electric current is utilized in electric bulbs for producing light. When electric current passes through a thin high resistance tungsten filament of an electric bulb, the filament becomes white hot and emits light.

The principle of electric fuse

An 'electric fuse' is an important application of the heating effect of current for safety. When the current drawn in an electric circuit increases beyond a certain value, the fuse wire gets over heated, melts and breaks the circuit. The fuse prevents fire and damage to various electrical appliances.