EMF – Investigation 3

Focus Questions

3-1  What is required to complete an electric circuit?

3-2 How does an electromagnet work?

3-3 What modifications to an electromagnet will affect the strength of its magnetic field?

Vocabulary

battery       circuit       component        constraint         contact point        core

electric current        electromagnet      electromagnetic force     filament

insulation      electromagnetic radiation     electromagnetism

energy transfer       engineer

Concepts

• 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.