The area, A, and the duration of contact, T, have been measured as a function of impact speed, U, for balls striking a flat surface. The balls lost about 40% of their kinetic energy over the range of speeds studied, but, surprisingly, the results for and appear to be consistent with Hertz’s elastic theory of impact. Possible reasons are discussed for this unexpected behavior.
REFERENCES
1.
J. F. Bell, “The experimental foundations of solid mechanics,” Handbuch der Physik (Springer-Verlag, Berlin, 1973), Vol. VIa/1, especially pp. 313–331.
An interesting comparison of the (elastic) impact of cylinders and balls is made by
D.
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[cf. also his later work on more complicated collisions,
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A. E. H. Love, A Treatise on the Mathematical Theory of Elasticity (Dover, New York, 1944), 4th ed., pp. 193–200, 440.
4.
L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics (Pergamon, Oxford, 1959), Vol. 7, pp. 26–31.
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J. P.
Andrews
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J. P.
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9.
G. W. C. Kaye and T. H. Laby, Tables of Physical Constants (Longmans, London, 1995), 16th ed., p. 48.
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R. F. S.
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2000
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