by
Earnest Garrison
The concepts of electricity and magnetism are usually taught separately. But I tend to think of them as being present at the same time ( not entirely correct but a lot of times true. The connection between electricity and magnetism becomes evident through the use of electromagnets. Here a coil of wire that has a current passing through it and a metal core is induced to produce a magnetic field. The field strength is directly proportional to the number of loops in the coil and the current in that passes through it. The section entitled more electromagnets contains a video about electromagnets.

1) What are the differences between permanent magnets and electromagnets ?
2) How is electricity flowing through a coil of wire used to make an electromagnetic ?
3) What is the differences between an electromagnetic that has DC current versus AC current ?
