question_answer 43)

  For a current in a long straight solenoid N and S-poles are created at the two ends. Among the following statements, the incorrect statement is (a) The field lines inside the solenoid are in the form of straight lines, which indicates that the magnetic field is the same at all points inside the solenoid (b) The strong magnetic field produced inside the solenoid can be used to magnetize a piece of magnetic material like soft iron, when placed inside the coil (c) The pattern of the magnetic field associated with the solenoid is different from the pattern of the magnetic field around a bar magnet (c) The N and S-poles exchange position when the direction of current through thesolenoid is reversed

Answer:

                  (c)Here, options (a), (b) and (d) are correct and knowledge based but option (c) is incorrect as the pattern of magnetic field inside a solenoid is uniform and similar to that of bar magnet. Also the one end of the solenoid behave as magnetic North Pole. While the other behaves as the South Pole.