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Resources: Electric and Magnetic Fields
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PowerPoint Lecture Notes: Electric and Magnetic Fields

References:

Here is a rare attempt to describe how, over the course of more than a century, our understanding of electricity and magnetism slowly developed (published by the electrical engineering professional society). But even this account gets ahead of itself by invoking concepts and information that did not exist at the time (such as the much later discovery of electrons):

The Long Road to Maxwell's Equations, IEEE Spectrum, December 2014 (link / cached copy)

 

Electric Fields:

YouTube movies of pith ball demonstrations:

 
Kahn Academy (silent) - YouTube link
 
Saint Mary's University - YouTube link

Carlton College (fully narrated) - YouTube link

 

Magnetic Fields:

My classroom demonstrations:

The effect of magnets upon metals:

This demonstrates the importance of containing iron (or iron-like metals = "ferromagnetics").

But it also shows that, despite containing 98-99% iron, the magnetism of steels can still be turned on or off by adding certain trace metals (as in various stainless steel alloys).

The effect of magnets upon magnets, compasses & iron filings => "Magnetic Fields"

(The "3D Magnetic Field Demonstrator" was purchased from Pasco Scientific (www.pasco.com) - P/N SE-8603)

 

Electro-magnetism:

The effect of electrical current upon a compass:

(coming soon)

(A home-built demonstrator)

 

Magnetic Induction:

Magnetic vs. non-magnetic ball falling through a long copper pipe I:

(This "Lenz Law Apparatus" was purchased from American Scientific (www.american-scientific.com) - P/N AR-105)

Magnetic vs. non-magnetic ball falling through a long copper pipe II:

(This "Lenz Law" apparatus was purchased from The Science Source (www.thesciencesource.com) - P/N 32520)

A long magnet falling through short aluminum pipe:

(coming soon)

(A home-built demonstrator)

The effect of moving magnets upon "non-magnetic" aluminum shapes:

(This demonstration combines the "Magnetic Force Accessory" & "Variable Gap Magnet" from Pasco Scientific (www.pasco.com) - P/N EM-8642A & EM-8618.
The railcar / rail assembly is a"video camera slider" purchased from B&H.com )

 

We Can Figure This Out. Org's movie studio (a.k.a., my basement wood/metal shop):

 

The use of magnetic induction to sort non-magnetic metals:

From the American Recycling Center:

(original link: https://www.youtube.com/channel/UCurq7PjCvPBx4zZ6v0i0wGw)

 

Copyright: John C. Bean (WeCanFigureThisOut.org)