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A solenoid has a fixed total number of turns and a fixed cross-sectional area. Its length L is changed by varying the spacing between successive turns. How does the inductance of the solenoid depend on L?
- Directly proportional to L
- Directly proportional to L²
- Inversely proportional to L²
- Inversely proportional to L
Correct answer: Inversely proportional to L
Solution
Inductance L = mu0*N^2*A/length. With the number of turns and area fixed, L is inversely proportional to the solenoid length.
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