Question

How to prepare an Electro Magnet.?

Answer 1

materials required 

1)insulated copper wire - thin insulation is best
2) a battery
3) a iron nail

step 1    coil the wire 

simply running the current through the wire produces a weak magnetic field 
but this is usually too weak to give us visable results. by coiling the wire closely we amplify the magnetic influence which  gives us visable results. the closer these windings are the better the electro magnet will be

step 2            making the magnet stronger

To make our electromagnet stronger we can give it an iron core. This will boost the power of our electromagnet and give us better results. This is as simple as winding the copper enamelled wire around an iron nail and securing it with sticky tape. When you connect it to a battery you will a have a stronger electromagnet. There are some simple things we can do to make our electromagnets stronger.

To make electromagnets stronger we must do the following:

Add more windings
Give it an iron core
Increase the current flowing through the wire