Q.
A tightly wound 100 turns coil of radius 10 cm carries a current of 7 A. The magnitude of the magnetic field at the centre of the coil is (Take permeability of free space as $4\pi\times10^{-7}$ SI units):
A) 4.4 mT
B) 44 T
C) 44 mT
D) 4.4 T
Explanation
[Solution by Claude - not from source] $B=\frac{\mu_0NI}{2r}=\frac{4\pi\times10^{-7}\times100\times7}{2\times0.1}\approx4.4\times10^{-3}$ T. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.