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Three infinitely long wires are placed equally apart on the circumference of a circle of radius a perpendicular to its plane. Two of the wires carry current $$l$$ each, in the same direction, while the third carries current 2$$l$$ along the direction opposite to the other two. The magnitude of the magnetic induction $$\overrightarrow {\bf{B}} $$ at a distancer from the centre of the circle for r > a, is

Three infinitely long wires are placed equally apart on the circumference of a circle of radius a perpendicular to its plane. Two of the wires carry current $$l$$ each, in the same direction, while the third carries current 2$$l$$ along the direction opposite to the other two. The magnitude of the magnetic induction $$\overrightarrow {\bf{B}} $$ at a distancer from the centre of the circle for r > a, is Correct Answer zero

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