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Alternating current cannot be measured by DIRECT CURRENT ammeter because

Alternating current cannot be measured by DIRECT CURRENT ammeter because Correct Answer Average value of current for complete cycle is zero

CONCEPT:

Ammeter:

  • It is a device used to measure current and is always connected in series with the ‘element’ through which current is to be measured.
  • The reading of an ammeter is always lesser than the actual current in the circuit.
  • Smaller the resistance of an ammeter more accurate will be its reading. 

EXPLANATION:

  • DC ammeter measures the average value over a cycle.
  • And in case of AC, the average value of the current over a cycle is zero. Hence we cannot measure AC current using DC ammeter. Therefore option 2 is correct.

Related Questions

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