Question

Due to the presence of the current I₁ at the origin

A current loop ABCD is held fixed on the plane of the paper as shown in the figure. The arcs BC (radius = b) and DA (radius = a) of the loop are joined by two straight wires AB and CD. A steady current I is flowing in the loop. Angle made by AB and CD at the origin O is 30°. Another straight thin wire with steady current I₁ flowing out of the plane of the paper is kept at the origin.

Answer 1

(b) : The straight wire is perpendicular to the segments and the fields are parallel. There will be no force. Due to parts AB and CD, their fields are equal and opposite and their effects also cancel each
other.