Asked by: Carel Lucas, Perth, Australia
Drift velocity, the average speed at which electrons travel in a conductor when subjected to an electric field, is about 1mm per second. It’s the electromagnetic wave rippling through the electrons that propagates at close to the speed of light. The dimensions of the wire and electrical properties like its inductance affect the exact propagation speed, but usually it will be around 90 per cent of the speed of light – about 270,000 km/s.
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