Field lines between like and unlike charges
Example a shows how the electric field is weak between like charges (the concentration of field lines is low between them). Example b, by contrast, has a strong field between the charges, as exhibited by the high concentration of field lines connecting them.
Source
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"OpenStax College, College Physics. December 29, 2012."
http://cnx.org/content/m42312/latest/?collection=col11406/latest
OpenStax CNX
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