The material testing protocol for a part calls for plane str

The material testing protocol for a part calls for plane stress conditions, so can be assumed that the part is in plane strain at the same time. True False The general Factor of Safety formula can be stated as: SF = sigma_allowable/sigma_yield SF = sigma_allowable/sigma_working SF = sigma_allowable/sigma_effective Both b and c The maximum principal stress criterion is ideal for predicting failure in duct materials. True False Is the following system statically determinate or indeterminate: Determinate Indeterminate Is the following system statically determinate or indeterminate: Determinate Indeterminate

Solution

1.6 True, Because plane stress is the state of stress in which normal stress and shear stress directed perpendicular to plane is assumed to be zero i.e if z-direction is perpendicular to x &y , then normal stress z , Shear stress yz and xz is zero.

But plane strain is defined as a state of strain in which the strain normal to the x-y plane i.e Z and the shear strains xz and yz are assumed to be zero.

1.7 b

1.8 False, according to the defination when the maximum principal stress in a complex stress system reaches the elastic limit stress in a simple tension, failure will occur. when is ideal for brittle material.

1.9 indeterminate, Because the total number of reaction components is not equal to the equations of equilibrium available.

r > 3n

r= reaction forces and n = no. of degree of freedom

1.10 determinate, Because the total number of reaction components is equal to the equations of equilibrium available.

r = 3n or r < 3n