Physics - Magnetism Question with Solution | TestHub

The magnetic field at $P$ due to current elements $\mathrm{PQ}$ and $PR$

is zero as the point $\mathrm{P }$is on the conductor. Therefore, the magnetic field at P due to current element $QR$ is

$\mathrm{B}=\frac{{\mu }_{0}I}{4\pi \left(PD\right)}\left[sin{\varphi }_1+sin{\varphi }_2\right]$

$=\frac{{\mu }_{0}1\times 5}{4\pi \times 12\mathrm{x}}\left[\frac{\left(\frac{9x}{5}\right)}{3x}+\frac{\left(\frac{16x}{5}\right)}{4x}\right]$

$=\frac{{\mu }_{0}I\times 5}{48\pi x}\left(\frac{3}{5}+\frac{4}{5}\right)$

$=\frac{7}{48}\frac{{\mu }_{0}I}{\pi x}$