DOMESTIC ELECTRIC CIRCUIT.pptx grade 10.

physics grade 10

1. DOMESTIC ELECTRIC CIRCUIT

2. Let’s study how electric circuit works in our home Electric power is generated by electric power stations These electric power stations pass curent through our homes by electric poles or underground cables Electric circuit reach our homes through main supply

3. Two Types Of Wire : Live Wires - Red colour insulation [ positive ] Neutral Wires - Black colour insulation [negative] Potential difference between live and neutral wire is 220 V These wires pass through main fuse or MCB These wires supply electricity to our homes

4. Two Circuits : 15 Ampere current rating appliances - They are used for appliances using high loads of electricity Eg.Electric iron , Geyser 5 Ampere current rating apppliances - They are used for appliances carrying low loads of electricity Eg . Tubelight , T.V

5. DIFFERNT SOCKETS IN A CIRCUIT There are mainly three sockets in a switch for connecting three main wires : Live wire -It is of red colour Neutral wire - It is of black colour Earth wire - It is of green colour

6. EARTH WIRE It is the third type of wire but it does not carry electricity . One end of earth wire is buried into the ground and the other end is connected to the metal casing of electrical appliances . If the live wire comes in contact with the metal case then current directly passes into the earth by the earth wire . It provides a low resistance conducting path for current . Hence earth wire is used to prevent people from electric shocks

7. OVERLOADING If too many appliances are used simultaneously [OR] If too many appliances are connected to a single socket they draw extremely large amount of current Due to this the wire may get overheated and may cause fire and start to burn This is overloading

8. SHORT CIRCUITING When live and neutral wire come in contact with each another they cause short circuiting . This happens if the insulation of both gets torn Due to high current to may start to catch fire and burn This can be prevented by a FUSE

9. FUSE A fuse is a device that is used in a circuit It prevents the damage to the circuit and overloading It stops the flow of unduly high electric current Nowadays MCBs are used instsed of fuse

10. MCB - Miniature Circuit Board If current becomes large ,MCB puts off a switch breaking of power supply These can be switched on again and reused

11. Difference between MCB and Fuse

12. QUESTIONS : Explain about short circuiting. Any three diffences between fuse and MCB What are the three types of wires used in a socket ? What happens in the earth wire ?