Q. The magnetic field at the centre of current carrying coil is
A) $\frac{\mu_{0}ni}{2r}$
B) $\frac{\mu_{0}}{2\pi}\frac{ni}{r}$
C) $\frac{\mu_{0}ni}{4r}$
D) $\mu_{0}ni$
Explanation
(a) Magnetic field at the centre of current carrying coil is
$B = \frac{\mu_{0}}{4\pi}.\frac{2\pi ni}{r} = \frac{\mu_{0}ni}{2r}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.