Why can’t an ordinary DC ammeter accurately measure alternating current (AC)?

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1. Why can’t an ordinary DC ammeter accurately measure alternating current (AC)?

AC simply cannot physically pass through a DC ammeter’s coil

The average value of a complete AC cycle works out to zero

AC is considered a ‘virtual’ rather than a real current

AC constantly changes its direction of flow

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A DC ammeter effectively responds to the average current over time. Since a symmetric AC waveform averages to zero across a full cycle, a simple DC ammeter shows no meaningful reading at all.