Teaching the Lorentz force, that magnetic fields apply perpendicular forces on moving charges, is often the first lesson of electromagnetism. It is a joy to share this unexpected behavior of magnets. Yet the students do not usually get to handle the apparatus, let alone build it. Typical demonstrations are cathode ray tubes, jumping wires, and possibly a lab using an e/m apparatus. In this article we discuss several other methods by which to provide hands-on demonstrations of the Lorentz force, most with simple equipment, and all that are intriguing and effective.

Topics
Display devices, Vacuum tubes, Electromagnetism, Electrostatics, Magnetic fields, Electric motors, Plasma confinement, Educational aids, Educational assessment, Teaching
1.
This article is accompanied by an online video abstract in which these and other Lorentz force demos are shown. The video can be viewed at TPT Online, http://dx.doi.org/10.1119/1.5131139 .
2.
See, for examples, the cover of the December 2006 issue of
The Physics Teacher
or
Marcelo
M. F. Saba
, “
Right-hand rule with magnet and monochrome monitor
,”
Phys. Teach
.
36
,
190
(
March
1998
).
https://doi.org/10.1119/1.880003
Google Scholar
Crossref
Search ADS
 
3.
Jeff
Tyson
 and
Carmen
Carmack
, “
How Computer Monitors Work
,” https://computer.howstuffworks.com/monitor7.htm.
4.
See
Dan
MacIsaac
, “
WebSights: Coolstuff video replicates the original Faraday motor in your class
,”
Phys. Teach.
50
,
189
(
Feb.
2012
).
https://doi.org/10.1119/1.3685130
Crossref
Search ADS
Google Scholar
 
Also, see
T. Walley
Williams
 III, “
Apparatus Drawings Project. Report Number 33. Simple apparatus for three lecture demonstrations
,”
Am. J. Phys.
31
,
42
(
Jan.
1963
) for a mercury version.
https://doi.org/10.1119/1.1969235
Crossref
Search ADS
Google Scholar
 
5.
See Nick Moore’s video of this: “
The Lorentz Force
,” YouTube, https://www.youtube.com/watch?v=8QWB8IfNoIs.
6.
Nick Moore has many other interesting demos on his channel http://youtube.com/nik282000.
© 2019 American Association of Physics Teachers.
2019
American Association of Physics Teachers
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