Some Shapes
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| Echinus (detail) Jean-Baptiste Lamarck (1744-1829), Tableau Encyclopédique et Méthodique des Trois Règnes de la Nature, Paris 1791-1798. Photograph by D Dunlop. |
A particle described by its wavelength $\lambda$ and orbital radius $\, R$ may be classified by shape.
| Shape | Definition |
| a point | $R = \lambda = 0$ |
| a line segment | $\lambda > R = 0$ |
| a plane section | $R > \lambda = 0$ |
| a plate | $R \gg \lambda > 0$ |
| a rod | $\lambda \gg R > 0$ |
| a cylinder | $\lambda \sim R > 0$ |
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Next step: displacement. |
page revision: 132, last edited: 17 Nov 2020 23:16
