A thin ring of $10\, cm$ radius carries a uniformly distributed charge. The ring rotates at a constant angular speed of $40\,\pi \,rad\,{s^{ - 1}}$ about its axis, perpendicular to its plane. If the magnetic field at its centre is $3.8 \times {10^{ - 9}}\,T$, then the charge carried by the ring is close to $\left( {{\mu _0} = 4\pi  \times {{10}^{ - 7}}\,N/{A^2}} \right)$

  • [JEE MAIN 2019]
  • A

    $2 \times {10^{ - 6}}\,C$

  • B

    $7 \times {10^{ - 6}}\,C$

  • C

    $4 \times {10^{ - 5}}\,C$

  • D

    $3 \times {10^{ - 5}}\,C$

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