why is it so??
Dear student,
Consider any element of the wire and current in it. We know from Lorentz force formula that a current in a magnetic field is associated with a force given as F = i l x B. Verify from the right hand thumb rule for the direction of the Lorentz force on that segment. The force would be either inward in the plane of the loop or outward in the plane of the loop. In both the case the loop would take shape with maximum area which is possible only when the shape is a circle.
Regards
Consider any element of the wire and current in it. We know from Lorentz force formula that a current in a magnetic field is associated with a force given as F = i l x B. Verify from the right hand thumb rule for the direction of the Lorentz force on that segment. The force would be either inward in the plane of the loop or outward in the plane of the loop. In both the case the loop would take shape with maximum area which is possible only when the shape is a circle.
Regards