understand how the use of insulation, double insulation, earthing, fuses and circuit breakers protects the device or user in a range of domestic appliance

understand why a current in a resistor results in the electrical transfer of energy and an increase in temperature, and how this can be used in a variety of domestic contexts

know and use the relationship between power, current and voltage:

power = current × voltage

\(P = I × V\)

and apply the relationship to the selection of appropriate fuses

use the relationship between energy transferred, current, voltage and time:

energy transferred = current × voltage × time

\(E = I × V × t\)

know the difference between mains electricity being alternating current (a.c.) and direct current (d.c.) being supplied by a cell or battery