Two circular coils X and Y have equal number of turns and carry equal currents in the same
sense and subtend same solid angle at point O. If the smaller coil X is midway between O and
Y, then if we represent the magnetic induction due to bigger coil Y at O as BY and that due
to smaller coil X at O as Bx :-

A thin flexible wire of length L is connected to two adjacent fixed points carries a current I in the clockwise direction, as shown in the figure. When system is put in a uniform magnetic field of strength B going into the plane of paper, the wire takes the shape of a circle. The tension in the wire is :-