Question

Consider the following two statements A and B and identify the correct answer.
A) When the length of a wire is doubled, the Young's modulus of the wire is also doubled
B) For elastic bodies Poisson's ratio is + Ve and for inelastic bodies Poissons ratio is -Ve

• A. Both A & B are true
• B. A is true but B is false
• C. A is true but B is true
• D. Both A & B are false

Answer 1

The correct option is D Both A & B are false

1/ Young's modulis is property of a metal independent of its dimensions
2/Definition of Poisson's ratio
Poisson's ratio is the ratio of transverse contraction strain to longitudinal extension strain in the direction of stretching force. Tensile deformation is considered positive and compressive deformation is considered negative. The definition of Poisson's ratio contains a minus sign so that normal materials have a positive ratio.Virtually all common materials, such as the blue rubber band on the right, become narrower in cross section when they are stretched.