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The total number of turns and cross-section area in a solenoid is fixed. However, its length l is varied by adjusting the separation between windings. The inductance of solenoid will be proportional to:
- l
- l²
- 1/l²
- 1/l
Correct answer: 1/l
Solution
Inductance L = mu0 N^2 A / l. With number of turns N and cross-section A fixed, L is proportional to 1/l.
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