Programmes 2 and 3 dealt with charges at rest. We now consider the effects of charges being in motion. Charges in motion give rise to what we call electric currents and these can be steady currents or currents which vary with time. In this programme we are concerned with steady currents by which we mean constant, direct currents. Time varying currents can have steady STATE values which means that the time variations are repeated periodically. Take care not to confuse the two. The fields associated with steady currents are static (i.e. constant with time).
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