Recall and use the equation power = current × voltage, P = IV

Define power as work done per unit time and also as energy transferred per unit time; recall and use the equations (a) power = work done / time taken, P = W/t (b) power = energy transferred / time taken, P = ΔE/t

Recall and use in calculations, the fact that: (a) the current at every point in a series circuit is the same (b) the sum of the currents entering a junction in a parallel circuit is equal to the sum of the currents that leave the junction (c) the total p.d. across the components in a series circuit is equal to the sum of the individual p.d.s across each component (d) the p.d. across an arrangement of parallel resistances is the same as the p.d. across one branch in the arrangement of the parallel resistances