It can be a challenge to come up with simple demonstrations of circular motion and conservation of energy. One such demonstration consists of a large exercise ball, off of which a small solid ball is rolled. The small ball is coated in finger paint so, after an initial push, it rolls nearly without slipping and creates a visible track.
References
1.
Herbert
Goldstein
, Charles
Poole
and John
Safko
, Classical Mechanics
, 3rd ed. (Addison-Wesley
, 2002
), p. 66
.2.
J.
Flores
, A. G.
del Rio
, A.
Calles
, and H.
Riveros
, “A simple problem in mechanics: A qualitative approach
,” Am. J. Phys.
40
, 595
–598
(April
1972
).3.
V.
Jayanth
, C.
Raghunadan
, and A.
Biswas
, “A sphere moving down the surface of a static sphere and a simple phase diagram
,” https://arxiv.org/abs/0808.3531.4.
Tom
Prior
and E. J.
Mele
, “A block slipping on a sphere with friction: Exact and perturbative solutions
,” Am. J. Phys.
75
, 423
–426
(May
2007
).5.
O. L.
de Lange
, J.
Pierrus
, Tom
Prior
, and E. J.
Mele
, “Comment on ‘A block slipping on a sphere with friction: Exact and perturbative solutions
’ by Tom
Prior
and E. J.
Mele
[Am. J. Phys.
75
(5
), 423
–426
(2007
)],”O. L.
de Lange
, J.
Pierrus
, Tom
Prior
, and E. J.
Mele
, Am. J. Phys.
76
, 92
(Jan. 2008
).6.
C. E.
Mungan
, “Sliding on the surface of a rough sphere
,” Phys. Teach.
41
, 326
–328
(Sept.
2003
).7.
R. A.
Bachman
, “Sphere rolling down a grooved track
,” Am. J. Phys.
53
, 765
–767
(Aug.
1985
).8.
Qing-Gong
Song
, “The requirement of a sphere rolling without slipping down a grooved track for the coefficient of static friction
,” Am. J. Phys.
56
, 1145
–1146
(Dec.
1988
).9.
D. C.
de Souza
and V. R.
Coluci
, “The motion of a ball moving down a circular path
,” Am. J. Phys.
85
, 124
–129
(Feb.
2017
).© 2020 American Association of Physics Teachers.
2020
American Association of Physics Teachers
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