A rigorous analysis of the bounce of a ball is complicated
by several factors, one being that in practice, a relatively soft
ball can easily squash to half its original diameter and also
squash asymmetrically, in which case the relation between
the compression of the ball and the displacement of its center
of mass is not easily determined. Another complicating fac-
tor is that the ball compression versus the applied force re-
lationship is not only nonlinear but may also vary with fre-
quency, in which case a static force versus compression
curve is not particularly relevant, and dynamic curves for a
spherical object are not readily available, if at all. A simple
experiment using a mass on the end of a rubber band is
described by Papadakis7 to illustrate the differences between
the dynamic and static properties of rubber. Even a steel ball
can be locally compressed beyond its elastic limit in a rela-
tively low-speed collision.2 Despite these complicating fac-
tors, the bounce of a ball can be analyzed at an elementary
level using a combination of elementary mechanics and ex-
perimental data on the force wave forms.
A rigorous analysis of the bounce of a ball is complicatedby several factors, one being that in practice, a relatively softball can easily squash to half its original diameter and alsosquash asymmetrically, in which case the relation betweenthe compression of the ball and the displacement of its centerof mass is not easily determined. Another complicating fac-tor is that the ball compression versus the applied force re-lationship is not only nonlinear but may also vary with fre-quency, in which case a static force versus compressioncurve is not particularly relevant, and dynamic curves for aspherical object are not readily available, if at all. A simpleexperiment using a mass on the end of a rubber band isdescribed by Papadakis7 to illustrate the differences betweenthe dynamic and static properties of rubber. Even a steel ballcan be locally compressed beyond its elastic limit in a rela-tively low-speed collision.2 Despite these complicating fac-tors, the bounce of a ball can be analyzed at an elementarylevel using a combination of elementary mechanics and ex-perimental data on the force wave forms.
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