Electricity in the home Flashcards
What is AC current
Alternating current
What is DC current)
Direct current
Explain what AC is
This is where the electrons move in 1 direction and then change direction and travel the opposite direction. The voltage will change from positive to negative and back again because of the different directions of current, giving it both a positive and negative directions.
Explain what DC is
Direct current is where the electrons only move in 1 direction around the circuit.
What is the peak voltage and frequency in the UK?
The peak voltage is 325v
(the average is 230v), and the frequency is 50 hertz.
What is the national grid and explain what it does?
The national grid distributes the electricity from power stations and transfers it to our houses. It is transferred at 100,000v which increases efficiency as less volts are lost.
What are transformers?
(step down/up) transformers are used to bring voltage up or down in an AC electrical circuit, this is so that electricity can be transported at a higher voltage and changed to lower so it’s not as dangerous in our homes.
Explain what these wires do and their colours:
- live wire
- neutral wire
- earth wire
Live wire: brown, carries electricity from the power station.
Neutral wire: blue, completes the circuit by carrying electricity back to the power station.
Earth wire: safety feature, grounds electricity.
List 3 home appliances at home that need an earth wire.
- oven
- washing machine
- dishwasher
List 3 appliances that are double insulated.
- hairdryer
- electric drills
- vacuum/hoover
Why is being shocked dangerous?
Being shocked is dangerous because it can cause harm to the body, if the shock is serious enough it’s able to cause the heart to stop and not restart immediately, leading to death.
What are the safety features of plugs?
Shutters on neutral and live wires, the current goes trough a fuse before Going to the live pin, the earth wire grounds electricity if the circuit blows, this prevents getting electrocuted, also the plug pins don’t touch.
Match the wire, it’s position and the colour.
Blue, green/yellow, brown
Earth, neutral, live
Right, left, top
Blue-neutral-left
Brown-live-right
Yellow/green-earth-top
What does a fuse do?
A fuse breaks a circuit if the current is too powerful and keeps electrical appliances safe from short circuits. They do this by melting the wire and stopping flow of electrons.
How do u measure the frequency of an AC supply?
Frequency =
1 /time taken for 1 cycle
