MAE 373 Ch4 SB

If a member is under a negative bending moment (M < 0), the center of curvature C due to the deformation is below the neutral surface, the anticlastic curvature p' would be _____ the neutral surface. - On - Below - Above - Aside

- Above

In the free body diagram of cantilevered beam shown, the internal force P' on the portion AC is ____ P. - Equal and parallel to - Equal and opposite to - Less than and opposite to - Larger than and opposite to

- Equal and Opposite to

The minus sign in the flexure formula, sigma x = - My / I, is so that positive z moment components generate tensile stresses ____ the neutral axis. - Above - Below - On

Below

*Image Required* For bending, the coordinate axis origin is placed on the neutral axis, DE. This placement insures that the location of the neutral axis remains _____ in all directions as shown in figure B.

Constant, unchanged, same

As shown in figure (b), the eccentric loading results in the presence of both a _____ and an axial tensile ____ on a section CC'.

Couple/Moment Force/Load

In pure bending, the actual distribution of stresses is statically _____. The actual stress distribution is obtained by analyzing the deformation in the member. - Nonexistent - Indeterminate - Determinate - Fixed

Indeterminate

A prismatic member in pure bending has equal and ____ couples acting in the same plane.

Opposite

*Image Required* The free body diagram for the hoisted barbell shown in the figure indicates section CD is in _____ _____.

Pure Bending

Which statement about plastic deformation and stress concentration is true? - Stress concentrations can make plastic deformations occur at lower loads. - The stress concentration factor takes into account any plastic deformation that occurs. - The values of maximum stress for plastic deformation and stress concentration are identical. - Stress concentrations will make plastic deformations occur at higher loads.

Stress concentrations can make plastic deformations occur at lower loads.

The members under pure bending are assumed to possess a plane of _____ with the couples acting on the plane.

Symmetry

*Image Required* For the pure bending stress state shown, if the sense of the moment were switched to be in the negative z direction, the elementary internal stress in the x direction above the centroid would be _____. - Shear stress in xy plane - Tension - Compression - Shear stress in the xz plane

Tension Tau of (xz) is in the z direction

Which statement is true with respect to stress concentration for the flat bar with fillets shown? - The stress concentration factor increases as the flat bar gets longer. - The stress concentration factor increases as the fillets to diameter ratio r/d gets larger - The stress concentration factor increases as the diameter ratio D/d gets larger, - The stress concentration factor increases as bending moment gets larger.

The stress concentration factor increases as the diameter ratio D/d gets larger.

The results from the direct applications of pure bending will be used in the analysis of other types of loadings, such as _____ loadings. - Compression - Transverse - Centric axial - Eccentric axial

Transverse Eccentric Axial

*Image Required* For pure bending shown, stress elements above the centroid are in _____ and stress elements below the centroid are in _____, with regard to normal stress.

compression, tension