Mechanics Exam MC Questions
The Poisson's ratio, v of common engineering materials lies in the range 0=< v =< ?
0.5
The principle of superposition is valid provided that: 1. The loading is linearly related to the stress or displacement 2. The loading does not significantly change the original geometry of the member 3. The Poisson's ration v=<0.45 4. Young's Modulus is small
1 2
In 3-D, ______ components of stress on each plane and totally there are _______ stress components for a state of stress
3 18
Which of the following statement is correct about polar moment of inertia? a. it only relates to the shape of the cross-section b. it is also a function of material property c. it is the same for a solid circular shaft and a tubular shaft d. large polar moment of inertia means large shear stress give the same torque
a
Which statement is not correct regarding the neutral axis of a beam (of a linear-elastic material) in pure bending? a. deflection of the neutral axis is zero b. neutral axis passes through the centroid of the section c. normal stress at neutral axis is zero d. normal strain at neutral axis is zero
a
stress is force acting on a/an ______ a. line b. area c. surface d. body
b
Provided that the bending formation of a straight member is small and within elastic range. Which of the following statements is incorrect? a. plane section remains plane b. cross section remains perpendicular to the longitudinal axis c. the length of the longitudinal axis remains unchanged d. in-plane distortion of cross section is not negligible
d
The modulus of elasticity E is a measure of the linear relationship between stress and strain. The common unit is: a. kN/mm^2 b. MPa c. GPa d. all of the above
d
The principle of superposition is applicable to: a. inelastic axial deformation b. residual stress evaluation c. large deformation d. none of the above
d
The stress distributions at different cross sections are different. However, at locations far enough away from the support and the applied load, the stress distribution becomes uniform. This is due to a. principle of superposition b. inelastic property c. Poisson's effect d. Saint Venant's Principle
d
What is the unit of strain? a. mm b. mm/m c. Micron d. no unit
d
Which of the following statements is incorrect for bending of a straight member? a. bending stress is proportional to the moment b. bending stress is inversely proportional to the second moment of area of the section c. bending stress is inversely proportional to the second moment of are of the section d. bending stress is not a function of the location
d
What type of stress will be induced on a cross-section by axial loading
normal stress
What type of stress will be induced on a cross-section by torsion?
shear stress
Where will the maximum shear stress occur on a cross-section during torsion?
surface of beam
