Question

A coil having $N$ turns carry a current as shown in the figure. The magnetic field intensity at point $P$ is:

• A. $\frac{{\mu }_{0}Ni{R}^2}{2{\left(R^2+x^2\right)}^{3/2}}$
• B. $\frac{{\mu }_{0}Ni}{2R}$
• C. $\frac{{\mu }_{0}Ni{R}^2}{(R+x{)}^2}$
• D. zero

Answer 1

Answer: (A)

From the formula, magnetic field intensity at point $P$, shown in given figure while coil carry current $i$ and having $N$ turns is given by
$\frac{{\mu }_{0}Ni{R}^2}{2{\left(R^2+x^2\right)}^{3/2}}$