(a) If the current carrying conductor is placed between the poles of magnet with its length in a direction such that the current in it is in the direction parallel to the direction of magnetic field then zero force acts on the wire and it does not move.
(b) If the current carrying conductor is placed between the poles of magnet with its length in a direction such that the current in it is in the direction perpendicular to the direction of magnetic field then maximum force acts on the wire.