Electric Shock and Muscular Contractions
An electric current can cause muscular contractions with varying effects. (a) The victim is "thrown" backward by involuntary muscle contractions that extend the legs and torso. (b) The victim can't let go of the wire that is stimulating all the muscles in the hand. Those that close the fingers are stronger than those that open them.
Source
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"OpenStax College, College Physics. November 12, 2012."
http://cnx.org/content/m42350/latest/?collection=col11406/1.7
OpenStax CNX
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