Q. A 250 - Turn rectangular coil of length 2.1 cm and width 1.25 cm carries a current of 85 μA and subjected to a magnetic field of strength 0.85 T. Work done for rotating the coil by 180° against the torque is :
A) 9.1 μJ
B) 4.55 μJ
C) 2.3 μJ
D) 1.15 μJ
Explanation
[Solution] $W = 2NIAB = 2 \times 250 \times 85 \times 10^{-6} \times 2.625 \times 10^{-4} \times 0.85 \approx 9.1$ μJ. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.