Voltmeter in Parallel
(a) To measure the potential difference in this series circuit, the voltmeter (V) is placed in parallel with the voltage source or either of the resistors. Note that terminal voltage is measured between points a and b. It is not possible to connect the voltmeter directly across the EMF without including its internal resistance, r. (b) A digital voltmeter in use
Source
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"OpenStax College, College Physics. October 25, 2012."
http://cnx.org/content/m42360/latest/?collection=col11406/latest
OpenStax CNX
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