The magnetic field ast a distance `x` on the axis of a circular coil of radius `R` is `1/8` th of that at the centre. The value of x is

Options

A. `R/sqrt3`
B. `(2R)/sqrt3`
C. `Rsqrt3`
D. `Rsqrt2`

Answer

C

Explanation

`B_x=1/8B_c`
`:. (mu_0NiR^2)/(2(R^2+x^2)^(3/2)=1/8[(mu_0Ni)/(2R)]`