The figure shows a circular loop of radius `a` with two long parallel wires `(numbered 1 and 2)` all in the plane of the paper . The distance of each wire from the centre of the loop is `d`. The loop and the wire are carrying the same current `I`. The current in the loop is in the counterclockwise direction if seen from above.
(q) The magnetic fields(B) at `P` due to the currents in the wires are in opposite directions.
(r) There is no magnetic field at `P`.
(s) The wires repel each other.

(4) When `d~~a` but wires are not touching the loop , it is found that the net magnetic field on the axis of the loop . In that case

Options

A. `(mu_(0)1^(2)a^(2))/(d)`
B. `(mu_(0)1^(2)a^(2))/(2d)`
C. `(sqrt(3)mu_(0)1^(2)a^(2))/(d)`
D. `(sqrt(3)mu_(0)1^(2)a^(2))/(2d)`

Answer

B