A part of a long wire carrying a current $i$ is bent into a circle of radius $r$ as shown in figure. The net magnetic field at the centre $O$ of the circular loop is
  • A$\frac{{{\mu _o}i}}{{4r}}$
  • B$\frac{{{\mu _o}i}}{{2r}}$
  • C$\frac{{{\mu _o}i}}{{2\pi r}}(\pi + 1)$
  • D$\frac{{{\mu _o}i}}{{2\pi r}}(\pi - 1)$
Medium
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