MCQ
Two thick wires and two thin wires, all of the same materials and same length form a square in the three different ways $P, Q$ and $R$ as shown in fig with current connection shown, the magnetic field at the centre of the square is zero in cases
  • A
    In $P$ only
  • B
    In $P$ and $Q$ only
  • C
    In $Q$ and $R$ only
  • $P$ and $R$ only

Answer

Correct option: D.
$P$ and $R$ only
$P$ and $R$ only

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