1. SYMBOLS
FUNCTION 1 2 3 4 5

2. SYMBOLS FUNCTION 6 7 8 9 10 A heater is designed to transfer
the energy from an electric current
to heat the surroundings. 9 10

3. Voltage, current and resistance
The (or cell) give the electrons
which are then pushed out along the wire.
battery
energy
The size of the push is called the
‘ ’ or voltage.
‘Potential difference’
Metals contain
free
electrons
Electrical is
moving electrons
current
The metal atoms (ions), slow down the electrons
causing This makes the bulb filament
resistance.
hot.
Word list: resistance current energy electrons battery ‘potential difference’ hot

4. At point P:
Current in at P =
Currents out at P

5. Bulbs in Series Bulbs in Parallel A A * Bulbs in series are dimly lit
* If one bulb breaks
the other goes out
* Bulbs in parallel are bright
* If one bulb breaks
the other stays on
Used in some Christmas tree lights
Used in houses and car head lamps