Question

What will be the reading of a d.c the ammeter in an a.c the circuit where the current flowing is $4\mathrm{A}$?

Answer 1

The reading of a d.c the ammeter in an a.c the circuit:

1. A d.c. ammeter is used to measure the average value of the direct current which has a fixed or positive magnitude.
2. But in a.c. circuits the current is oscillating in nature so the average value of current will be always zero over a complete cycle.
3. Any amount of a.c. currents can not be measured by a d.c. ammeter.
4. Also the d.c. current has frequency zero.

Therefore, there will always be $0$ reading in the d.c. ammeter for any magnitude of the current flowing in the a.c. circuit.