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A current of – 8 + 6√2 (sin ωt + 30°) A is passed through three meters. They are a centre zero PMMC meter, a true rms meter and a moving iron instrument. The respective readings (in A) will be
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- 8, 6, 10
- 8, 6, 8
- – 8, 10, 10
- – 8, 2, 2
Correct Option: C
PMMC instrument reads only DC value and since it is centre zero type so it will give – 8 value. RMS meter will read rms value of the current, so
| RMS = √(8)² + |  |  | ² | = 10A | |
| √2 |
A. Moving iron also reads rms value, so its reading will also be 10 A.
Hence ultimately it will be – 8, 10, 10.
