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 ?

The electron drift speed is estimated to be only a few mm s^(-1)for cu

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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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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