Electricity in the home Flashcards
(24 cards)
National grid voltage
Has to be really high to minimise energy loss
Where do we get most of our energy from?
Power stations that generate a lot of heat and converting thermal energy into electrical energy
What does the nation grid contain
- step up/down transformers
- pylons
- wires
What is the UK main supply
- 50 hz
- 240 V
AC produced by???
Alternating pd
DC produced by??
direct potential difference
brown wire
live wire
Blue wire
neutral wire
Green and yellow wire
earth wire
live wire
provides the alternating potential difference from main supply
neutral wire
Complete the circuit by carrying away current
Earth wire
stop the applicance casing from becoming live
How does an electric shock happen?
our body is at 0V so if you touch something with a large potential difference, a current flows through you causing an electric shock
How does earth wire prevent an electric shock?
provides a alternative pathway for the current to flow away
surges
sudden increase in current
how do fuses work?
- a very thin piece of wire connected to live wire and if there’s a surge the wire will heat up and melt
- break circuit
benefits of fuses
- simple
- cheap
downsides of fuses
- permanently broken after single surge
- have to be replaced each time
Circuit breakers
- they get tripped when a surge flows
- turns off the circuit
- can be resetted
double insulate
where the appliance is covered in a plastic casing so there’s no exposed metal parts
static electricity
Build up of charge on insulating materials and causes spark when discharged
Why does conducting material never has charge?
The electrons are able to flow back again
polythene rod
electrons move from the insulating material to the rod
Acetate rod
electrons moves from the rod to the duster
