ENG1001 Tutorial 3

A material is called isotropic if...

• It deforms equally in all directions under a uniaxial load

• It has the same material properties in all directions

• its Young's modulus is equal to the shear modulus

• its Young's modulus is equal to the bulk modulus

Which of these materials is isotropic?

• Wood

• Steel

• Graphite

• Glass

Given an isotropic and linear elastic material, the relationship between shear modulus G and Young's modulus E is...

•  $G\ =\frac{E}{2\left(1+\nu\right)}$  

•  $G\ =\ \frac{\nu}{2\left(1+E\right)}$  

•  $G=\frac{2\nu}{1+E}$  

•  $G=\frac{E}{2+2\nu}$  

The Poisson ratio $\nu$ is a measure of a material's...

• deformation in the direction of a uniaxial load

• deformation in the direction transverse to a uniaxial load

• deformation in the direction tangent to a uniaxial load

• deformation in the direction perpendicular to a uniaxial load

An isotropic material with Poisson ratio $\nu>0$ is compressed under a uniaxial load. Its transverse strain is...

• positive

• negative

• zero

A material has a Poisson ratio of $\nu=0.5$ . The material is:

• homogeneous

• isotropic

• incompressible

• anisotropic

You're asked to compute the shear stress  $\tau$ for the shape shown. Which face should you use to calculate the cross-sectional area $A_0$ ?

• A

• B

• C

An object is submerged in a body of water. Which of the elastic properties is most relevant to this situation?

• Young's modulus

• Shear modulus

• Bulk modulus

• Poisson ratio