A uniform current carrying ring of mass $m$ and radius $R$ is connected by a massless string as shown. A uniform magnetic field $B_0$ exist in the region to keep the ring in horizontal position, then the current in the ring is  ($l =$ length of string)
  • A$\frac{{mg}}{{\pi R{B_0}}}$
  • B$\frac{{mg}}{{R{B_0}}}$
  • C$\frac{{mg}}{{3\pi R{B_0}}}$
  • D$\frac{{mgl}}{{\pi {R^2}{B_0}}}$
Medium
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