Question

what is a poisson's ratio..??explain briefly

Answer 1

Poisson's ratio is the ratio of transverse contraction strain to longitudinal extension strain in the direction of stressing force.Tensile deformat is considered positive and compressive deformation is considered to be -ve. The definition if Poisson's ratio contain  a minus sign so that normal material have positive ratio. Poisson's ratio is also called Poisson coefficient .
n = - ∈trans / ∈longitudinal
where                                                                                                                         n = Poisson's ratio                                                                                                      ∈t = transverse strain                                                                                                ∈l = longitudinal or axial strain

Answer 2

poisson ratio is transrve ratio  contraction strain to longitudinal extension strain in the direction of stressing force.Tensile deformat is considered positive and compressive deformation is considered to be -ve. The definition if Poisson's ratio contain  a minus sign so that normal material have positive ratio. Poisson's ratio is also called Poisson coefficient .