Electric Current and its Effect

From an electric pole or underground cables, we receive electric supply in our homes. Domestic electric circuit consists of three main wires. The wire with red insulation is called live wire. The wire with black insulation is called neutral wire. Potential difference between the neutral and the live wire is 220 V.The wire with green insulation is called earth wire. It is connected to a metallic body deep inside the earth.According to new International Convention, insulation of live wire should be of brown colour whereas neutral and earth wires should be of light blue and green (or yellow) insulation cover. In our homes, we receive AC electric power of 220 V with a frequency of 50 Hz. Live wire and neutral wire maintains the p.d. of 220 V. These wires pass through the fuse board. Fuse is specially connected with the live wire. Current rating of this fuse depends on house load. From the fuse board, these wires pass through the electric metre. From the metre, the earth wire is locally inserted inside the ground of the house. After the electric metre, these wires pass through the main switches and fuses in different rooms. Depending on the power of electrical appliances, two types of fuse (5A or 15 A) are used. From the switch and fuse board, the power lines are distributed to different electrical appliances.

When an electric current flows through a wire, the wire gets heated. It is the heating effect of current or When current flows through a metal wire it gets heated up, this is called heating effect of current. E.g. a glowing electric bulb becomes warm. This effect has many applications like Electric Heater, Light Bulb etc.

When an electric current flows through a wire, it produces magnetic effect around it. A current carrying coil of an insulated wire wrapped around a piece of iron is called an electromagnet. Magnetic Effect of electric current has many applications like Electric Bell, Motor, Fan etc