Shear Modulus - Explanation

Explanation

Material Typical values for
shear modulus (GPa)
Diamond 478.
Steel 79.3
Copper 44.7
Titanium 41.4
Glass 26.2
Aluminium 25.5
Polyethylene 0.117
Rubber 0.0006
Glycerin 0.000000255
Water 0.00000000016

The shear modulus is one of several quantities for measuring the stiffness of materials. All of them arise in the generalized Hooke's law:

  • Young's modulus describes the material's response to linear strain (like pulling on the ends of a wire or putting a weight on top of a column),
  • the bulk modulus describes the material's response to uniform pressure (like the pressure at the bottom of the ocean or a deep swimming pool)
  • the shear modulus describes the material's response to shearing strains (like cutting it with dull scissors).

The shear modulus is concerned with the deformation of a solid when it experiences a force parallel to one of its surfaces while its opposite face experiences an opposing force (such as friction). In the case of an object that's shaped like a rectangular prism, it will deform into a parallelepiped. Anisotropic materials such as wood, paper and also essentially all single crystals exhibit differing material response to stress or strain when tested in different directions. In this case one may need to use the full tensor-expression of the elastic constants, rather than a single scalar value.

Read more about this topic:  Shear Modulus

Famous quotes containing the word explanation:

    My companion assumes to know my mood and habit of thought, and we go on from explanation to explanation, until all is said that words can, and we leave matters just as they were at first, because of that vicious assumption.
    Ralph Waldo Emerson (1803–1882)

    The explanation of the propensity of the English people to portrait painting is to be found in their relish for a Fact. Let a man do the grandest things, fight the greatest battles, or be distinguished by the most brilliant personal heroism, yet the English people would prefer his portrait to a painting of the great deed. The likeness they can judge of; his existence is a Fact. But the truth of the picture of his deeds they cannot judge of, for they have no imagination.
    Benjamin Haydon (1786–1846)

    Are cans constitutionally iffy? Whenever, that is, we say that we can do something, or could do something, or could have done something, is there an if in the offing—suppressed, it may be, but due nevertheless to appear when we set out our sentence in full or when we give an explanation of its meaning?
    —J.L. (John Langshaw)