A classical mechanical structure with an internal degree of freedom is shown to reflect off a potential well. Such behavior is impossible for point-like or rigid classical particles. This numerical study provides insight for students studying internal energy and degrees of freedom.

1.
T. W. B.
Kibble
and
F. H.
Berkshire
,
Classical Mechanics
(
Addison-Wesley Longman
,
Harlow, UK
,
1996
), Chap. 2.
2.
D.
Morin
,
Introduction to Classical Mechanics
(
Cambridge University Press
,
Cambridge, UK
,
2007
), Chap. 5.
3.
A. P.
French
,
Newtonian Mechanics
(
W.W. Norton
,
New York
,
1971
), Chap. 5.
4.
There is a quantum phenomenon equivalent to reflecting off a barrier of lower energy: passing through a barrier of higher energy. This phenomenon is known as tunneling and is purely quantum mechanical—there is no classical equivalent. For a classical system that is claimed to exhibit tunneling, see
A.
Cohn
and
M.
Rabinowitz
, “
Classical tunneling
,”
Int. J. Theor. Phys.
29
,
215
223
(
1990
).
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