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कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

The self inductance L of a solenoid of length l and area of cross-section A, with a fixed number of turns N increases as ______.

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प्रश्न

The self inductance L of a solenoid of length l and area of cross-section A, with a fixed number of turns N increases as ______.

विकल्प

  • l and A increase.

  • l decreases and A increases.

  • l increases and A decreases.

  • both l and A decrease.

MCQ
रिक्त स्थान भरें
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उत्तर

The self inductance L of a solenoid of length l and area of cross-section A, with a fixed number of turns N increases as l decreases and A increases.

Explanation:

The self inductance L of a solenoid depends on various factor like geometry and magnetic permeability of the core material.

L = μrμ0 N2 Al

Where n = N/l (no. of turns per unit length)

  1. No. of turns: Larger the number of turns in solenoid, larger is its self inductance.
  2. Area of cross-section: Larger the area of cross-section of the solenoid, larger is its self inductance.
  3. Permeability of the core material. The self inductance of a solenoid increases μr times if it is wound over an iron core of relative permeability μr.

The long solenoid of cross-sectional area A and length l, having A turns, filled inside of the solenoid with a material of relative permeability (e.g., soft iron, which has a high value of relative permeability) then its self inductance is L = μrμ0 N2 A/l

So, the self inductance L of a solenoid increases as l decreases and A increases because L is directly proportional to the area and inversely proportional to length.

Important point: The self and mutual inductance of capacitance and resistance depend on the geometry of the devices as well as permittivity/ permeability of the medium.

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अध्याय 6: Electromagnetic Induction - MCQ I [पृष्ठ ३४]

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एनसीईआरटी एक्झांप्लर Physics Exemplar [English] Class 12
अध्याय 6 Electromagnetic Induction
MCQ I | Q 6.06 | पृष्ठ ३४

संबंधित प्रश्न

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