As shown in the figure, two infinitely long, identical wires are be...

As shown in the figure, two infinitely long, identical wires are bent by \( 90^{\circ} \) and placed in such a way that the segments
\( L P \) and \( Q M \) are along the \( x \)-axis, while segments \( P S \)
and \( Q N \) are parallel to the \( y \)-axis. If \( O P=O Q=4 \mathrm{~cm} \)
and the magnitude of the magnetic field at \( O \) is \( 10^{-4} \mathrm{~T} \) and
the two wires carry equal currents (see figure), the
magnitude of the current in each wire and the direction of
the magnetic field at \( O \) will be
(a) \( 40 \mathrm{~A} \), perpendicular out of the page
(b) \( 40 \mathrm{~A} \), perpendicular into the page
(c) \( 20 \mathrm{~A} \), perpendicular out of the page
(d) \( 20 \mathrm{~A} \), perpendicular into the page