• An electric circuit is a system that includes a complete pathway through which electric current flows.
• A magnetic field surrounds a wire through which an electric current is flowing.
• The magnetic field produced by a current-carrying wire can induce magnetism in a piece of iron or steel.
• An electromagnet is made by sending electric current through an insulated wire wrapped around an iron core.
• The strength of magnetism induced in the core of an electromagnet increases with the number of winds of wire, the amount of electric current flowing through the wire, and the iron content of the core.