MCQ
Mark the incorrect statement.
  • A
    The direction of the magnetic field is taken to be the direction in which a north pole of the compass needle moves inside it.
  • B
    The magnetic field lines are closed curves.
  • C
    No two field-lines are found to cross each other.
  • D
    None

Answer

  1. None

Explanation:

The direction of the magnetic field is taken to be the direction in which a north pole of the compass needle moves inside it. Therefore it is taken by convention that the field lines emerge from the north pole and merge at the south pole. Inside the magnet, the direction of field lines is from its south pole to its north pole. Thus the magnetic field lines are closed curves. The relative strength of the magnetic field is shown by the degree of closeness of the field lines. The field is stronger, that is, the force acting on the pole of another magnet placed is greater where the field lines are crowded. No two field-lines are found to cross each other. If they did, it would mean that at the point of intersection, the compass needle would point towards two directions, which is not possible.

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