Alternating current cannot be measured by a D | vedclass

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(B) In a $DC$ ammeter,a coil is free to rotate in the magnetic field of a fixed magnet.If an alternating current is passed through such a coil,the tor

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The average value of a complete cycle is zero.

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(B) In a $DC$ ammeter,a coil is free to rotate in the magnetic field of a fixed magnet.If an alternating current is passed through such a coil,the torque will reverse its direction each time the current changes direction.Since the frequency of $AC$ is typically high,the coil cannot follow the rapid changes in torque due to its inertia.Consequently,the average value of the torque over a complete cycle is zero,and the pointer remains at the zero position.

Alternating current cannot be measured by a $DC$ ammeter because:

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