Q. A current carrying straight wire is kept along the axis of a circular loop carrying a current. The straight wire
A) Will exert an inward force on the circular loop
B) Will exert an outward force on the circular loop
C) Will exert a force on the circular loop parallel to itself
D) Will not exert any force on the circular loop
Explanation
(d) According to Fleming’s left hand rule, direction of magnetic field at the centre $O.$
The force on the current carrying conductor is $F = i\mathbf{dl} \times \mathbf{B}$ [image:4_image97.emf]
As angle between $dl$ and B is zero
$\therefore\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ F = 0$
The straight with will not exert any force on the circular loop.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.