Question: A PMMC instrument produces a deflection of 90° when a current 2 mA passes through its moving coil. The instrument is spring controlled. Suppose the instrument is redesigned with its spring constant as before, and its permanent magnet is replaced with a new permanent magnet which produces twice the flux density as before. what would be the deflection if a current of 1 mA is passed through the coil ? The other features of the PMMC instrument remain the same.
Answer:
MCQ: A PMMC instrument produces a deflection of 90° when a current 2 mA passes through its moving coil. The instrument is spring controlled. Suppose the instrument is redesigned with its spring constant as before, and its permanent magnet is replaced with a new permanent magnet which produces twice the flux density as before. what would be the deflection if a current of 1 mA is passed through the coil ? The other features of the PMMC instrument remain the same.
Correct Answer:
A. 180°
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Related Questions
- 1. A 1 mA ammeter has a resistance of 100 Ω.it is to be converted to a 1 A ammeter. The value of shunt resistance is :
- 2. Swamping resistance is connected
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