ELECTRICITY

Electricity 

>Current:


Current is the rate of flow of charge;

Electric charge is movement of electrons;

To measure current we use ammeter and it’s unit is amperes or amps or A;

The ammeter should be connected in series in a a circuit  the current should flow through positive terminal of an ammeter and leave through the negative terminal;

Voltage provides the pressure that makes the current flow and to complete the circuit;

This must need for a current to flow;

If there are any breaks in the circuit, in fact that’s how a switch works.

That’s why there is switch in the appliances to get off and its prevents the current from flowing .

To calculate the current in the circuit we can use this formula :

                    Charge,Q

Current, I =—————

                      Time, t 

             

Charge, Q = current I x time, t 


> Wires: 

  If see a 3 pin plug they have different wires and 2 pins plugs are almost same

So, the 3 pin plug have 3 different wires that are :

The live wire which is in brown colour and the earth wire which is in green and yellow colour and last neutral wire which is in blue colour ;

The brown live wire and the blue neutral wire carry the current around the circuit ;

The live wire is a route into the plug for the electric current the current is an alternating current which travels back and forth approximately 50 times a second; 

The neutral wire completes the circuit it is the route the electric current tapes when it exits in an appliance neutral wires have a voltage close to zero;

The green and yellow earth wire is a safety wire many electrical appliances have metal casings if they lose wire touches the metal casing anyone who touches the appliances get an electric shock which is where the earth wire comes in the earth wire connects to the earth pin which takes the current away from the appliance into the wiring of your house and down to the earth through the houses earthing system so the current runs through the earth wire rather than running through you if you touch the appliance much much safer the earth pin on a plug is longer than the live and neutral pins therefore whenever you plug in a plug the earth pin always connects with the socket first providing you with the earthing safety.


>fuse: the main role of the fuse is to save and prevent fires starting due to large currents, another safety feature is the outer insulation of wires attach the plug plastic is an electric insulator meaning electricity cannot travel through it if the electrical wire is surrounded by a plastic casing then they are safe to touch if there is break in the plastic or it is damaged you could come into contact with the wire inside and have an electric shock so do yourself a favour if your phone charger is broken get yourself a new one. Fuse’s a low melting point so if to larger current flows through the fuse then the wire heats up and melts thus breaking the circuit which is why you might you hear the phrase the fuse has blown if there is a gap in the circuit electricity cannot flow and so the device will not work but the user is safe. Fuse is very thin and it is between the live terminal and the live pin.

So the different countries have different colours of the wire and the different the size of the pins.

But is pretty much the same. 



It is very much easy to remember the where the wire is assembled you can take an example from the colour of the wire so, the blue where the letter in blue L represents left and brown where the letter in the brown R represents right and the mix yellow and green in the striped form in the word stripped letter T represents the top.

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