Chapter 14: Electric Current and its Effects

Chapter 14: Electric Current and its Effects

Wires made from some special materials melt quickly and break when large electric currents are passed through them. These materials are used for making electric fuses which prevent fires and damage to electric appliances. When an electric current flows through a wire, it behaves like a magnet.

Symbols of electric components

Heating effects of electric current

When an electric current is passed through a conductor, the conductor becomes hot after some time and produces heat. The reason for this change in temperature is the transformation of some electric energy passing through the conductor into heat energy.

Magnetic effect of electric current

Electric current has two effects; heating effect and magnetic effect. This happens because a magnetic field is generated around the wire as electric current passes through a conductive wire. The magnetic field causes the magnetic compass to deflection.

Electromagnetic

Electromagnetism is a branch of physics involving the study of the electromagnetic force, a type of physical interaction that occurs between electrically charged particles. The electromagnetic force is carried by electromagnetic fields composed of electric fields and magnetic fields, and it is responsible for electromagnetic radiation such as light. It is one of the four fundamental interactions (commonly called forces) in nature, together with the strong interaction, the weak interaction, and gravitation. At high energy, the weak force and electromagnetic force are unified as a single electroweak force.

Electric Bell

An electric bell is a mechanical or electronic bell that functions by means of an electromagnet. When an electric current is applied, it produces a repetitive buzzing, clanging or ringing sound. Electromechanical bells have been widely used at railroad crossings, in telephones, fire and burglar alarms, as school bells, doorbells, and alarms in industrial plants, since the late 1800s, but they are now being widely replaced with electronic sounders. An electric bell consists of one or more electromagnets, made of a coil of insulated wire around an iron bar, which attract an iron strip armature with a clapper.