How do we protect ourselves from the dangers of electricity?

Pupils should:

(a) understand the roles of the live, neutral and earth leads and insulation in domestic electrical circuits.

(b) know how the earth lead and fuse operate to protect consumers against fire and electrical shocks.

(c) select and use the equation:

current  = power/ voltage

to calculate the current taken by the appliance in normal use and hence the correct fuse required to protect the cable to the appliance.

(d) explain the roles of miniature circuit breakers (m.c.b.) and residual current devices(r.c.d.) and compare their actions to those of fuses.

(e) discuss how ideas of risk and cost play a part in deciding what voltage domestic electricity supplies should use and appreciate that different countries have adopted different voltages.