7. Specific Gravity
Specific gravity of a substance is its density
relative to that of water and is a pure number.
Specific gravity is also called relative density.
8. Elasticity
Stress is the magnitude of force applied in a
body divided by the area over it is exerted.
Three Categories:
1. Tensile stress
2. Compressive stress
3. Shear stress
9. Hooke’s Law
Hooke’s Law states that the amount of deformation
experienced by a body under stress is proportional to
the magnitude of the force applied to it.
11. Properties of Materials
Ductility is the property of metals which can
be deformed beyond the elastic limit.
Malleability is the property of metals which
has a large plastic range in compression
Ductility is the property of metals that has a
large plastic range in tension.
17. Young’s Modulus
For tensile or compressive stresses, the modulus of elasticity
is called Young’s Modulus.
Young’s modulus depends on the composition of the material.
23. Shear
Shear stresses change the shape of an object on which they
act but not on its volume.
Angle of shear is the measure of the relative distortion of the
block caused by the shear stress.
24. Shear Modulus
Shear Modulus or sometimes referred to as Modulus
of Rigidity is the ratio of shear stress to shear strain.
The higher the value of shear modulus, the more
rigid the material.
