Deformation of Solids

1
Deformation of Solids

• Stress is proportional to Strain
• stress elastic modulus strain
• The SI unit for stress is the Newton per meter
  squared (N/m2), which is also called the Pascal
  (Pa)

2
Youngs Modulus elasticity in length

• When an object is stretched (compressed)
  lengthwise.
• Tensile Stress
• Y is called Youngs Modulus, Lo is the original
  length, and DL is the change in length.

3
Fig. 12.14, p.373
4
Fig. 12.15, p.374
5
Shear Modulus elasticity of shape

• Shear stress occurs when a force acts parallel to
  the surface of an object
• Shear Stress
• S is the shear modulus, Dx is the horizontal
  distance the sheared face moves, h is the height
  of the object.

6
Fig. 12.16, p.374
7
Bulk Modulus volume elasticity

• Volume stress has to do with uniform squeezing
  (like when an object is submersed in a fluid).
• Volume Stress
• B is the bulk modulus, DV is the change in
  volume, and V is the original volume.
• The negative sign is there because an increase in
  the pressure will decrease the volume.

8
Fig. 12.17, p.375
9
Table 12.1, p.374
10
Fig. 12.18, p.376