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JEE Main20199 Apr 2019Morning ShiftPhysicsElectromagnetic InductionActual

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:

Options

  1. AL
  2. B1 L 2
  3. C1 L
  4. DL 2

Correct answer

C. 1 L

Step-by-step solution

Self-Inductance = μ 0 n 2 π r 2 L (n = number of turns per unit length) = μ 0 N L 2 π r 2 L = μ 0 N 2 π r 2 L Self-Inductance ∝ 1 L

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