Text: "What do 'voltmeters' measure?: Faraday's law in a multiply connected region." A long solenoid carrying a varying current produces a time-dependent magnetic field and induces electric fields, even in the region external to the solenoid where the time rate of change of B, and therefore curl E, vanish. Two identical voltmeters, both connected to the same two points in the circuit, may not show identical readings. American Journal of Physics. 50(12), Dec. 1982. p. 1089-1093.

See Also: Bohm-Aharonov effect, magnetic vector potential, voltage, measurement , scalar fields, shadow vector, Faraday's law, electric fields.

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