Electricity and circuit
Electric cell:-
👉Electricity to the bulb in a torch is provided by the electric cell. Electric cells are also used in alarm clocks, wristwatches, transistor radios, cameras and many other devices.
👉All electric cells have two terminals :-
- a positive terminal
- a negative terminal
👉An electric cell produces electricity from the chemicals stored inside it. When the chemicals in the electric cell are used up, the electric cell stops producing electricity.
Electric circuit:-
When electric components like bulb, cells, wires, etc. are connected with each other, the setup is called an electric circuit.
A bulb lights up only when electric current passes through the circuit.
Note :- In an electric circuit, the direction of current is taken to be from the positive to the negative terminal of the electric cell.
Fused :– Sometimes an electric bulb does not glow even if it is connected to the cell. This may happen if the bulb has fused.
Reason for fused :- An electric bulb may fuse due to many reasons. One reason for a bulb to fuse is a break in its filament.
A break in the filament of an electric bulb means a break in the path of the current between the terminals of the electric cell. Therefore, a fused bulb does not light up as no current passes through its filament.
Switch :- A switch is a simple device that either breaks the circuit or completes it.
Conductor :- Materials which allow electric current to pass through them are conductors of electricity.
Insulator :- Materials that do not allow electric current to pass through them are called insulators.
Note :- Switches, electrical plugs and sockets are made of conductors. On the other hand, rubber and plastics are used for covering electrical wires, plug tops, switches and other parts of electrical appliances, which people might touch.