MCQ
Alternating current can not be measured by dc ammeter because
- A$ac$ cannot pass through dc ammeter
- ✓Average value of complete cycle is zero
- C$D.C.$ ammeter will get damaged.
- D$ac$ changes its direction
✓
Answer
Correct option: B.
Average value of complete cycle is zero
b
(b)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.
(b)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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