MHT CET · Physics · Electromagnetic Induction
A coil is wound on a core of rectangular crosssection. If all the linear dimensions of the core are increased by a factor 2 and number of turns per unit length of coil remains same, the self inductance increases by a factor of (Assume, permeability is same)
- A 16
- B 8
- C 4
- D 2
Answer & Solution
Correct Answer
(B) 8
Step-by-step Solution
Detailed explanation
The self-inductance of the coil is given by
\(\mathrm{L}=\mu_0 \mathrm{n}^2 l \mathrm{~A}\)
When n is kept constant and linear dimensions is increased by a factor of 2, the area of cross-section will become 4 A and length with become \(2 l\).
\(\therefore \quad\) Self-inductance will become 8 times.
\(\mathrm{L}=\mu_0 \mathrm{n}^2 l \mathrm{~A}\)
When n is kept constant and linear dimensions is increased by a factor of 2, the area of cross-section will become 4 A and length with become \(2 l\).
\(\therefore \quad\) Self-inductance will become 8 times.
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