Question

A circular coil of wire of radius ' $r$ ' has ' $n$ ' turns and carries a current '$I$'. The magnetic induction ' $B$ ' at a point on the axis of the coil at a distance $\sqrt{3}r$ from its centre is

• A. $\frac{{\mu }_{0}nI}{16r}$
• B. $\frac{{\mu }_{0}nI}{4r}$
• C. $\frac{{\mu }_{0}nI}{32r}$
• D. $\frac{{\mu }_{0}nI}{8r}$

Answer 1

Answer: (A)

$B=\frac{{\mu }_{0}ni{r}^2}{2{\left(x^2+r^2\right)}^{3/2}}$