The standard low-friction tracks used to test Newton's laws are the air track and the low-friction cart track. Both are commercially available and provide low-friction environments to test various physics concepts. At a recent science fair, one of the authors (JG) presented a magnetically levitated cart and track. A literature search found no previous testing of magnetically levitated carts.1 This paper compares a magnetically levitated cart against the two standard low-friction tracks.

1.
A reviewer of this paper noted that using an Internet search engine revealed web articles describing the construction of magnetically levitated carts. Two are provided here: http://amasci.com/maglev/train.html and http://my.execpc.com/∼rhoadley/magtrain.htm.
2.
Barbara S.
Andereck
, “
Measurement of air resistance on an air track
,”
Am. J. Phys.
67
(
6
),
528
533
(June
1999
).
3.
P.
Theodórsson
, “
A new dynamics cart on an inclined plane
,”
Phys. Teach.
33
,
458
459
(Oct.
1995
).
4.
Roger F.
Larson
, “
Measuring the coefficient of friction of a low-friction cart
,”
Phys. Teach.
36
,
464
465
(Nov.
1998
).
5.
Louis H.
Cadwell
, “
Magnetic damping: Analysis of an eddy current brake using an air track
,”
Am. J. Phys.
64
(
7
),
917
923
(July
1996
).
6.
Due to the relatively large friction of the magnetic cart, a level was used (as opposed to the no-motion method usually used with air tracks) to level all the tracks. Thank you to the editor for noting the 1% contribution of the pulley to the result.
This content is only available via PDF.
AAPT members receive access to The Physics Teacher and the American Journal of Physics as a member benefit. To learn more about this member benefit and becoming an AAPT member, visit the Joining AAPT page.