الفهرس 
ContentsOnly 14 pages are availabe for public view
 |  | from | 141 |  |  |
| | | from | 141 | | |
Abstract
Almost all engineering materials possess to a certain extent the property of elasticity.if the external forces producing deformation do not exceed a certain limit,the deformation disappears with the removal of the forces.the bodies undergoing the action of the external forces are called perfectly elastic,when theey resume their initial from completely after removal of these forces.historically,robert hooke first announcedthe notion of elasticity in 1678.