The core of a coil has a length of 200 mm. The inductance of coil is 6 mH. If the core length is doubled, all other quantities, remaining the same, the inductance will be_____________?
Correct answer: A. 3 mH
- A. 3 mH
- B. 12 mH
- C. 24mH
- D. 48mH
Explanation
For a coil on the same core, inductance is inversely proportional to magnetic-path length, L ∝ 1/l. Doubling the core length therefore halves 6 mH to 3 mH.
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