What is the reason that alternating current cannot be measured by a DC ammeter?
Answer & explanation
Correct answer: option 4
Alternating current cannot be measured by D.C ammeter because A.C. current have alternating signs and average value of current for complete cycle is zero and practical frequencies are like 50-60 Hz that means it changes signs more than 100 times a second which is not visible on D.C. ammeters.