Q.
A current of 10 A is passing through a long wire which has semicircular loop of the radius 20 cm as shown in the figure. Magnetic field produced at the centre of the loop is
A) $10\ \pi\mu\ tesla$
B) $5\ \pi\mu\ tesla$
C) $4\ \pi\mu\ tesla$
D) $2\ \pi\mu\ tesla$
Explanation
(b) $B = \frac{40}{4\pi} \times \frac{\pi i}{r} = 10^{- 7} \times \frac{\pi \times 10}{20 \times 10^{- 2}}\ 5\pi\mu\ tesla$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.