Magnetic field

Magnetic field

This is the space around a magnet where the strength of the magnet is felt.

Magnetic field line- An imaginary line along the direction of force of the magnetic field. Their closeness is a measure of the strength of the magnetic field or of the force that would be exerted by the bar magnet.

Characteristics of magnetic field lines

               i.    Magnetic field lines of force start from the North Pole and end at the South Pole.

              ii.    Magnetic lines of force cannot intersect each other.

            iii.    They are closer where the field is stronger

             iv.    They repel each other sideways and form closed paths without intersecting

Magnetic field patterns

 

 

Magnetic shielding

This is where magnetic field is prevented from reaching certain regions.

  

The points marked ‘X’ are called neutral points where there is no magnetic field at such points. Watches (non-digital), electron beams in cathode ray tubes and TV sets are shielded from external magnetic fields by placing a soft-iron cylinder around the neck of the tube or watch.