Summary AQA GCSE Physics Electricity Topic - UK Mains

ELECTRICITY
physics



UK ELECTRICITY
AC-
- Is an AC (alternating current) supply
Alternating current – - Frequency of 50Hz
current continuously varies
from positive to negative
- Potential Difference of 230V
charge

DC-
Earth wire Live wire
Direct current – the current
moves in one direction
only

Example: batteries Neutral Fuse
wire

Cable
grip


Outer
insulation


Brown (live) wire –

230V, carries the potential difference from the supply, should never touch the brown wire
because it can cause a fire or a shock

Blue (neutral) wire –

0V, completes the circuit

Yellow and green (Earth) wire – carries a current only if there is a fault, provides a low
resistance path to the ground (current takes the path of least resistance) this protects the
person from an electric shock

Fuse –

The fuse will melt if the current going through is too great. This will break the circuit and
protects the wiring and appliance.




ENERGY TRANSFERRED EQUATION ENERGY TRANSFERRED EQUATION
energy transferred = charge * time energy transferred = charge * potential difference

E = Pt E = QV

E = energy transferred in Joules (J) E = energy transferred in Joules (J)

P = power in Watts (W) Q = charge in Coulombs (c)

t = time is seconds (s) V = potential difference in Volts (V)