In a power transformer, the fundamental frequency of the hum arising due to magnetostriction is

In a power transformer, the fundamental frequency of the hum arising due to magnetostriction is 

(a) equal to the line frequency (b) double the line frequency (c) 4 times the line frequency (d) not related to the line frequency
by

1 Answer

Answer :

In a power transformer, the fundamental frequency of the hum arising due to magnetostriction is double the line frequency

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