Electricity Flashcards
(17 cards)
1
Q
Heating effect
A
- wire has resistance
- electrons collide with lattice of ions in coil
- so they transfer energy as they travel through the wire
- increases thermal energy
- increasing temperature means quicker vibrations
- slower flow of electrons = more resistance
2
Q
Fuse
A
- Fault develops and the live wire touches the metal casing
- Surge of current sent through the live wire
- fuse melts
- break in the cicruit means no current is flowing - appliance is isolated
3
Q
Live Wire
A
Brown
4
Q
Earth Wire
A
Yellow/Green
5
Q
Neutral wire
A
Blue
6
Q
Double Insulation
A
No Earth Wire
Plastic is an insulator
7
Q
Fuses vs Circuti breakers
A
Fuses
- have to be replaced
- detect large changes in current
Circuit breakers
- dont have to be replaced - switch opens when current increases
- more sensitive to small changes in current
8
Q
Series Circuit
A
- voltage splits
- current stays the same
9
Q
Parrallel Circuit
A
- Voltage stays the same
- current splits
10
Q
Series Advantages
A
- less wires
- one switch
- less likely to overheat
11
Q
Series Disadvantages
A
- one bulb goes they all go
12
Q
Parrallel advantages
A
- one bulb goes the others still work
13
Q
Parallel disadvantages
A
- harder and complicated to set up
- lots of wires
- likely to overheat
14
Q
Light Dependent resistor
A
Resistance increase in dark
Resistance decreases in light
15
Q
Thermistor
A
Resistance increases in cold
Resistance decreases in hot
16
Q
Current
A
Rate of flow of charge
17
Q
Volatage
A
Energy transferred per unit charge
Volt = a joule per coloumb
