MCQ
There will be no force between two wires carrying currents if currents are:
  • A
    Parallel to each other
  • B
    Antiparallel to each other
  • C
    Perpendicular to each other
  • D
    None of these.

Answer

  1. Perpendicular to each other

Explanation:

Force on a current carrying wire placed in a magnetic field is given by F = I (l × B) So when the wires are perpendicular the magnetic field produced by one of them will be along the length of the other and we know cross product of two vectors along the same direction is zero.

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