The current in flowing along the path $ABCD$ of a cube (shown in the left figure) produces a magnetic field at the centre of cube of magnitude $B$. Dashed line depicts the non-conducting part of the cube.

Consider a cubical shape shown to the right which is identical in size and shape to the left. If the same current now flows in along the path $DAEFGCD$, then the magnitude of magnetic field at the centre will be

• A

  zero
• B

  $\sqrt{2}B$
• Correct answer
  C

  $\sqrt{3}B$
• D

  $B$

Hence, the correct answer is option: 'C'.