Q. A circular loop of radius 0.0175$m$ carries a current of 2.0 amp. The magnetic field at the centre of the loop is $(\mu_{0} = 4\pi \times 10^{- 7}weber/amp - m)$
A) $1.57 \times 10^{- 5}\ weber/m^{2}$
B) $8.0 \times 10^{- 5}\ weber/m^{2}$
C) $2.5 \times 10^{- 5}\ weber/m^{2}$
D) $3.14 \times 10^{- 5}\ weber/m^{2}$
Explanation
(b) $B = \frac{\mu_{0}}{4\pi}\frac{2\pi i}{r} = 10^{- 7} \times \frac{2\pi \times 2}{0.0157} = 8 \times 10^{- 5}Wb/m^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.