In our daily life we use electricity for various activities. The electric lamps andtubes light our houses, we listen music on a tape recorder or radio, see differentprogrammes on television, enjoy cool breeze from electric fan or cooler, and useelectric pump to irrigate fields. In fact, electricity is a unique gift of science tomankind. We can not imagine life without electricity in the modern world. Athome you might have observed that as soon as you switch on an electrtc lamp, itstarts glowing. Why does it happen? What is the function of a switch?

The electric lamp starts glowing as soon as you switch it on because of the flow of electric current. When the switch is off, the circuit is open and no current flows through it. But when you turn the switch on, you close the circuit, allowing electric current to flow through the lamp. This current provides the energy needed for the lamp to glow.

The function of a switch in an electrical circuit is to control the flow of electricity. It does this by opening (turning off) or closing (turning on) the circuit. When the switch is closed, electricity can flow freely through the circuit, powering any devices connected to it. When the switch is open, the flow of electricity is stopped, turning off the devices.