MCQ
Alternating current can not be measured by dc ammeter because
- Aac cannot pass through dc ammeter
- ✓Average value of complete cycle is zero
- Cac is virtual
- Dac changes its direction
✓
Answer
Correct option: B.
Average value of complete cycle is zero
In $d c$ 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 it's direction each time the current changes direction and the average value of the torque will be zero.
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