What is a solenoid? Draw the pattern of magnetic field lines of (i) a current carrying solenoid and (ii) a bor magnet. List two distinguishing features between the two fields.

What is a solenoid? Draw the pattern of magnetic field lines of (i) a

1.	What is a solenoid? Draw the pattern of magnetic field lines of (i) a current carrying solenoid and (ii) a bor magnet. List two distinguishing features between the two fields.
Answer» Solution :A solenoid is a LONG cylindrical coil with many close turns of insulated copper wire wrapped in the shapw of a CYLINDER. (i) MAGNETIC field lines of current carrying solenoid: (ii) Magnetic fiedl lines of a bar magnet. See Q. 21(a), 2018 (Comptt.). Distinguishing features between the two fields: (a) The strength of magnetic field DUE to SLOENOID can be changed while the magnetic field strength due to bar magnet cannot be changed. Solenoid produses magnetic field as long as current flows in its coils while bar magnet produces a permanent magnetic field.