How do current of the circuit affect the magnitism of the nail

[vvc531]

I am doing a lab these days
its about how the current of the circuit affect the magnitism of the nail (rapped with wire around it)
I wonder if anyone has the relation or some info related to it.

 

[mukrajat]

I think your question is unclear, but I will make an assumption that i know what you are asking and proceed. please correct me if wrong.

assumption: you have wrapped a coil around a conducting (iron) nail, and are passing current through the coil.

well, if there is no insulation between the two, you effectively have a short circuit.

if there is an insulation, as the the current in the coil increases, it will induce an opposite sense current in the nail to try to cancel out the growing flux of the coil. when the current becomes steady state, no more current will flow in the nail. Accordingly, you will have created a N-S magnetism field along the length of the nail.

now conducting materials like the nail are theorized to be ferromagnetic materials. i.e., they are said to include dipoles that are highly susceptible to magnetic fields. As you can imagine, your current carrying coil will magnetize the nail in the same sense as the coil was magnetized.

More about ferromagnetism here:http://en.wikipedia.org/wiki/Ferromagnetic

 

[confinement]

In 99% of cases the magnetic field strength is proportional to the current in the wire, the exceptions are for more complicated materials/conditions.