Poisson's ratio is a material property that describes the relationship between a material's deformation in response to applied stress. It is the ratio of the transverse strain (lateral contraction) to the axial strain (longitudinal extension) when a material is subjected to tensile or compressive stress.
The change in volume of a material can be calculated using Poisson's ratio by multiplying the original volume by the change in length and width, and dividing it by the elastic modulus and 1 minus the Poisson's ratio.
Knowing the variation in volume of a material is important in understanding its behavior under stress and predicting potential structural failures. It can also help engineers design more efficient and durable structures.
Poisson's ratio can be determined experimentally by applying uniaxial stress to a material and measuring the change in lateral and axial strains. The ratio can also be calculated by measuring the change in volume of a material under stress and comparing it to the change in length and width.
No, Poisson's ratio cannot be negative as it represents the relationship between two positive quantities (transverse and axial strains). A negative value would indicate that the material is expanding laterally when subjected to tensile stress, which is physically impossible.