Electrons Moving Through a Conductor
When charged particles are forced into this volume of a conductor, an equal number are quickly forced to leave. The repulsion between like charges makes it difficult to increase the number of charges in a volume. Thus, as one charge enters, another leaves almost immediately, carrying the signal rapidly forward.
Source
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"OpenStax College, College Physics. October 26, 2012."
http://cnx.org/content/m42341/latest/?collection=col11406/1.7
OpenStax CNX
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