As shown in the figure, two infinitely long, identical wires are bent by $90^o$ and placed in such a way that the segments $LP$ and $QM$ are along the $x-$ axis, while segments $PS$ and $QN$ are parallel to the $y-$ axis. If $OP = OQ = 4\, cm$, and the magnitude of the magnetic field at $O$ is $10^{-4}\, T$, and the two wires carry equal current (see figure), the magnitude of the current in each wire and the direction of the magnetic field at $O$ will be $(\mu_ 0 = 4\pi \times10^{-7}\, NA^{-2})$

820-1101

  • [JEE MAIN 2019]
  • A

    $20\, A$, perpendicular out of the page

  • B

    $40\, A$, perpendicular out of the page

  • C

    $20\, A$, perpendicular into the page

  • D

    $40\, A$, perpendicular into the page

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