MCQ
In the given figure net magnetic field at O will be
  • A
    $\frac{2 \mu_0 \mathrm{i}}{3 \pi \mathrm{a}} \sqrt{4-\pi^2}$
  • $\frac{\mu_0 \mathrm{i}}{3 \pi \mathrm{a}} \sqrt{4+\pi^2}$
  • C
    $\frac{2 \mu_0 \mathrm{i}}{3 \pi a^2} \sqrt{4+\pi^2}$
  • D
    $\frac{2 \mu_0 \mathrm{i}}{3 \pi \mathrm{a}} \sqrt{4-\pi^2}$

Answer

Correct option: B.
$\frac{\mu_0 \mathrm{i}}{3 \pi \mathrm{a}} \sqrt{4+\pi^2}$
(b) $\frac{\mu_0 \mathrm{i}}{3 \pi \mathrm{a}} \sqrt{4+\pi^2}$

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