Question

A wire carrying a current of $4\sqrt{5}$ amperes is bent into the form of a circle of radius 5 cm. The flux density at a distance of 10 cm on the axis passing through the centre of the coil and perpendicular to its plane is

• A. $8\pi \times 10^{-3}T$
• B. $4\pi \times 10^{-3}T$
• C. $8\pi \times 10^{-5}T$
• D. $4\pi \times 10^{-5}T$

Answer 1

Answer: (C)

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