• Electiricity: It is a flow of electic current.
• Electric Current: The Electic current flows around by Electric Circuit.
• Electric Circuit: In a closed electric circuit, the electric current passes from one terminal of the electric cell to the other terminal.
• Circuit Diagram: It is a symbolic representation of the electric circuit.
• Component of Electricity:
(i) Connecting wires: Help to conduct the electric current and complete the circuit.
(ii) Bulb: Lights up when an electric current flows through it. An electric bulb has a filament that is connected to its terminals. An electric bulb glows when electric current passes through it.
(iii) Switch: Switch is a simple device that is used to either break the electric circuit or to complete it. When a switch is on, a gap in the circuit is bridge by a conducting material through which the current flows.
(iv) Electric cell: An electric cell has two terminals; one is called positive (+ ve) while the other is negative (– ve).
• Connecting wires, bulb, switch and electric cell is used in Torch, Battery, LED (Light Emitting Diode), etc.
• Electric current is carried by Conductor.
• Conductor: Materials that allow electic current to pass through them. All metals are good conductors of electricity. Carbon is the only non-metal which is a good conductor of electricity.
• Electric current is stopped by Insulators.
• Insulators: Materials which do not allow electric current to pass through them. Example: plastic, rubber, wood, glass, polythene, PVC, etc.