Topic 2b- Domestic electricity Flashcards
1
Q
What are the two types of electricity supplies?
A
AC/DC
Alternating current/ direct current
2
Q
What cables connect most appliances to the mains supply- what colours and voltages are they at?
A
3 core cables:
- Live wire (brown- 230V)
- Neutral wire (blue- 0V)
- Earth wire (green and yellow- 0V)
3
Q
What is the function of the earth wire?
A
To protect the wiring and for safety. Stops the appliance casing from becoming live. It carries current only when there’s a fault.
4
Q
What is the AC voltage in the UK?
A
230V
5
Q
What current do cells and batteries use?
A
Direct current (DC)
6
Q
What must be done to electricity on the national grid?
A
Potential difference must be stepped up when travelling in the wires, and stepped down when it reaches consumers.
7
Q
How efficient are transformers?
A
Almost 100% efficient
