Is simple shear same as rotational strain? or, is it a type of rotational strain?
More on http://en.wikipedia.org/wiki/Shear_stress" [Broken].
More on http://en.wikipedia.org/wiki/Strain_(materials_science)#Strain".
Put simply, shear is a stress applied parallel or tangential to the surface of a material, while normal stress is applied perpendicularly. The units are force/area.
Strain, on the other hand, is the measure of deformation in the material, and those units are in length/length (it's a dimensionless quantity).
Thus, for any given amount of sheer, the harder the material, the less the strain.
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