A circular current carrying coil has a radius $R$. The distance from the centre of the coil on the axis where the magnetic induction will be $\frac{1}{8}^{th}$ to its value at the centre of the coil, is

  • A

    $\frac{R}{{\sqrt 3 }}$

  • B

    $R\sqrt 3 $

  • C

    $2\sqrt 3 \,R$

  • D

    $\frac{2}{{\sqrt 3 }}R$

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