An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be 

(1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field

1 Answer

Answer :

An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be either decreased or increased depending on the direction of the DC field

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