Hooke's Law	1R10.10 Hooke's Law
Tensile and Compressive Stress	1R20
Shear Stress	1R30
Coefficient of Resitution	1R40.10 Bouncing Balls
	1R40.30 Dead and Live Balls
Crystal Structure	1R50.20 Bravais Lattice Models
	1R50.20 Crystal Models