-Why must you use an iron core to make an electro magnet? Why can you use things like plastic or aluminum?
-Why must you wind the wire in the same direction around the iron core to make make the electromagnet.
-What happend if some of the wire is wound in one direction and some of the wire is wound in the other direction?
-How could you make an electromagnet stronger?
I would greatly appreciate any input and Thanks for your help in advance.