Charge Distribution on a Conductor with an Irregular Surface
Curvature causes electric field lines to extend such that they further distance themselves from one another with increasing distance from the conductor surface. As such, charges (and field lines) aggregate around areas of curvature.
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"OpenStax College, Conductors and Electric Fields in Static Equilibrium. January 9, 2013."
http://cnx.org/content/m42317/latest/
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