Jefferson Lab's Workbench Projects
An electromagnet is formed when a current carrying wire is wrapped around an iron core. The strength of the electromagnet depends on, among other things, the number of times the wire is wrapped around the core and the amount of current that is flowing through the wire. The Electromagnet Experiment Stand is a device that demonstrates the relationship between the strength of an electromagnet and the number of coils wrapped around its core as well as the relationship between the strength of an electromagnet and the amount of current flowing through its coils.
If this project looks too complex, instructions for building a simple electromagnet can be found on this page: