Question

When the iron fillings are placed on a cardboard through which a current carrying wire passes the iron aligns itself on the magnetic field lines.

why does the iron not accumulate in the Space between the two lines? Is it because the magnetic effect does not work over there or some other reason? Explain in detail

Answer 1

Basically iron fillings do not leave space, space is created when iron fillings line up with magnetic field. The curved path along which the iron filling arrange themselves due to the force acting on them in the magnetic field. Here, each piece of iron filing becomes small magnet and experience a force in certain direction in the magnetic field due to which they align themselves along the magnetic field lines not in random space between them.

Closer the magnetic field lines more is the magnetic field strength. So less space between the two lines will be there if magnetic field is stronger and vice versa. So we can have any number of lines depending upon the strength of magnetic field and hence the arrangement of iron fillings.

Note: If you put a large amount of fillings, space between two magnetic field lines would not be visible because all the fillings would not be able to arrange themselves end to end due to magnetism induced in them.