JEE Mains · Physics · STD 12 -6. Electromagnetic induction
A copper wire is wound on a wooden frame, whose shape is that of an equilateral triangle. If the linear dimension of each side of the frame is increased by a factor of \(3\), keeping the number of turns of the coil per unit length of the frame the same, then self inductance of the coil
- A decreases by a factor of \(9\)
- B increases by a factor of \(27\)
- C increases by a factor of \(3\)
- D decreases by a factor of \(9\sqrt 3 \)
Answer & Solution
Correct Answer
(C) increases by a factor of \(3\)
Step-by-step Solution
Detailed explanation
Total length \(L\) will remain constant \(\mathrm{L}=(3 \mathrm{a}) \mathrm{N} \quad(\mathrm{N}=\text { total tums })\) And length of winding \(=(d) N=\ell\) \((d=\text { diameter of wire })\) Self inductance \(=\mu_{0} \mathrm{n}^{2} \mathrm{A} \ell\)…
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