JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
A regular polygon of \(6\) sides is formed by bending a wire of length \(4 \pi\) meter. If an electric current of \(4 \pi \sqrt{3} \mathrm{~A}\) is flowing through the sides of the polygon, the magnetic field at the centre of the polygon would be \(x \times 10^{7} \mathrm{~T}\). The value of \(\mathrm{x}\) is ______.
- A \(72\)
- B \(75\)
- C \(80\)
- D \(82\)
Answer & Solution
Correct Answer
(A) \(72\)
Step-by-step Solution
Detailed explanation
\(s = \frac{P}{n} = \frac{4\pi}{6} = \frac{2\pi}{3} \mathrm{~m}\) \(a = \frac{s}{2 \tan(\pi/n)} = \frac{2\pi/3}{2 \tan(\pi/6)} = \frac{2\pi/3}{2(1/\sqrt{3})} = \frac{\pi\sqrt{3}}{3} \mathrm{~m}\)…
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