P5 - Electricity in the Home Flashcards
1
Q
What is frequency and what is it measured in?
A
- Frequency is the number of waves per time period
- It is measured in hertz
2
Q
What is the frequency and equivalent voltage of the mains supply in the UK?
A
-50 Hz or 230 V
3
Q
What are the three wires in a plug?
A
- Live wire
- Earth wire
- Neutral wire
4
Q
What does the live wire do?
A
-The live wire carries the alternating potential difference from the supply.
5
Q
What does the earth wire do?
A
-The earth wire is a safety wire to stop the appliance becoming live.
6
Q
What does the neutral wire do?
A
-The neutral wire completes the circuit.
7
Q
What is power?
A
-Amount of energy transferred per second.
8
Q
How do you work out power?
A
-Energy transferred / time taken
9
Q
How else can you calculate power?
A
- Current x potential difference
- Current^2 x resistance
10
Q
How do you calculate charge flow?
A
-Current x time
11
Q
How do you calculate energy?
A
-Potential difference x charge flow
