Question

For current in a long straight solenoid, North and South poles are created at the two ends. Among the following statements, the incorrect statement is

• A. The field lines in a solenoid, as well as a bar magnet form, closed loops.
• B. A solenoid can be used to magnetise a piece of magnetic material like iron.
• C. The pattern of the magnetic field of a solenoid and bar magnet are not identical.
• D. The poles of a solenoid are reversed if the direction of current through it is reversed.

Answer 1

The correct option is C

The pattern of the magnetic field of a solenoid and bar magnet are not identical.

A current carrying solenoid behaves like a bar magnet with fixed polarities at its ends. The field lines of a solenoid are also very much like that of a bar magnet, where it originates from the north pole and moves towards the south pole outside the magnet and moves from south to north inside the magnet. These field lines form closed loops.

A solenoid produces a magnetic field, any magnetic material such as iron placed in the magnetic field is magnetized.