Natural materials do not have a negative density or a negative bulk modulus, but, negative values are mathematically possible, and can be demonstrated when dispersing soft rubber in a liquid.
42.
Hence, there is a narrow range of normalized frequency 0.035 < ?a / ( 2?c ) < 0.04 where the bulk modulus and negative density are both negative.
43.
The bulk modulus of water is about 2.2 GPa . The low compressibility of non-gases, and of water in particular, leads to their often being assumed as incompressible.
44.
The monopolar resonance creates a negative bulk modulus above the normalized frequency at about 0.035 while the dipolar resonance creates a negative density above the normalized frequency at about 0.04.
45.
This has the same form as the acoustic wave equation in one-dimension . c _ L is determined by properties ( bulk modulus B and density \ rho ) of the structure according to
46.
Its bulk modulus at 1000 & deg; F ( 538 & deg; C ) is 310, 000 psi ( 2.14 GPa ), higher than of a hydraulic oil at room temperature.
47.
Rhenium diboride also has a reported bulk modulus of 383 GPa and a shear modulus of 273 GPa . The hardness of rhenium diboride, and most other materials also depends on the load during the test.
48.
For ideal gases the bulk modulus " K " is simply the gas pressure multiplied by the dimensionless adiabatic index, which is about 1.4 for air under normal conditions of pressure and temperature.
49.
Hardness of a material to deformation is dependent on its microdurability or small-scale shear modulus in any direction, not to any rigidity or stiffness properties such as its bulk modulus or Young's modulus.
50.
Shear modulus is related to bulk modulus as 2B ( 1 " 2v ) ( 1 + v ) } }, where v is the Poisson s ratio, which is typically ~ 0.1 in covalent materials.
