Electrical Charge at a Sharp Point of a Conductor
Forces between like charges at either end of the conductor are identical, but the components of the forces parallel to the surfaces are different. The component parallel to the surface is greatest on the flattest surface and therefore moves charges away from one another more freely. This explains the difference in concentration of charge on flat vs. pointed areas of a conductor.
Source
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"OpenStax College, College Physics. December 28, 2012."
http://cnx.org/content/m42317/latest/?collection=col11406/latest
OpenStax CNX
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