In Textual Example 1, the electron drift speed is estimated to be only a few mm s^(-1) for currents in the range of a few amperes? How then is current established almost the instant a circuit is closed?

In Textual Example 1, the electron drift speed is estimated to be only

1.	In Textual Example 1, the electron drift speed is estimated to be only a few mm s^(-1) for currents in the range of a few amperes? How then is current established almost the instant a circuit is closed?
Answer» Solution :Electric FIELD is established throughout the circuit, almost instantly (with the speed of light) (CAUSING at every point a LOCAL electron drift.Establishment of a current does not have to wait for ELECTRONS from one end of the conductor travelling to the other end. However it does take a little while for the current to reach its steady value.

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In Textual Example 1, the electron drift speed is estimated to be only a few mm s^(-1) for currents in the range of a few amperes? How then is current established almost the instant a circuit is closed?

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