Properties of an electromagnet

[Jaymo3141]

We are going over magnetism in my Physics 2 course but we barely covered electromagnets. I was wondering what the math equation for field strength would be for an electromagnet. In other words, how is current related to field strength when you wrap a wire around a piece of metal. Also I was wondering because i wanted to experiment with a high powered magnet. Like a car battery. Too dangerous?

 

[mfb]

You can find many relevant formulas at Wikipedia or in all textbooks about electromagnetism.

Also I was wondering because i wanted to experiment with a high powered magnet. Like a car battery. Too dangerous?

I would be worried about the car battery. The magnetic field itself, if it is far away from anything reacting to magnetic fields, should be fine.