Electricity And Electromagnetism Flashcards
1
Q
What is the point of an earth wire?
A
It conducts the electricity which draws a large current from the live wire causing the fuse to break
2
Q
What is the equation for power?
A
Power=current x voltage
3
Q
What is the difference between AC and DC?
A
DC is the current flowing in one direction only
AC is when a current switches direction constantly
4
Q
What is the equation for resistance?
A
R=V/I
5
Q
What are the four factors affecting resistance?
A
- Resistance increases with length
- As width/area increases, resistance decreases
- Copper is a good conductor
- Resistance increases with temperature
6
Q
What colour is the neutral wire?
A
Blue
7
Q
What colour is the earth wire?
A
Green/yellow
8
Q
What colour is the live wire?
A
Brown
9
Q
Define voltage
A
The energy transferred per unit passed
10
Q
How is static electricity caused?
A
- Two insulators are rubbed together
- Makes one positive and the other negative
- These attract small objects
