大学MOOC Engineering Mechanics(Northwestern Polytechnical University)1458261168 最新慕课完整章节测试答案

Appendix A Moments of Areas

1、单选题：
​If the section figure has a symmetry axis, then for the figure (    ) to its symmetry axis.‍
选项：
A: Both the static moment of inertia and the moment of inertia are not zero;
B: Both the static moment of inertia and the moment of inertia are zero;
C: The static moment of inertia is not zero, the moment of inertia is zero;
D: The static moment of inertia is zero, the moment of inertia is not zero.
答案: 【 The static moment of inertia is zero, the moment of inertia is not zero.】

2、单选题：

‌The area of the graph is A , the  axis pass through the centroid C and parallel to the  axis, the distance between  axis and the  axis is . It is known that the moment of inertia of the graph with respect to  axis is , and the moment of inertia of the graph with respect to  axis is (     ).

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‌

‏选项：
A: ;
B: ;
C: ;
D: .
答案: 【 ;】

3、单选题：
​ Let the moment of inertia of the rectangle to its symmetric axis Z is I. When the ratio of length to width remains unchanged and the area is doubled, the moment of inertia of the rectangle to its symmetric axis Z will become (     ).‍
选项：
A: 2I ;
B: 4I ;
C: 8I ;
D: 16I .
答案: 【 4I ;】

4、单选题：

‏For the figure as shown, if the centroidal axis Z divides the figure into two parts, then ( ) must be established.

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‍选项：
A:         

B:
C:
D:
答案: 【 】

5、判断题：
‍In the geometric properties of planes, the values of static moment of inertia and moment of inertia can be positive, negative and zero.​
选项：
A: 正确
B: 错误
答案: 【 错误】

Chapter 10 Internal Forces in Bending

1、单选题：

‏In the following figures, figure (    ) shows that the bending moment M on the section is positive and the shear force  is negative .

‏选项：
A:
B:
C:
D:
答案: 【 】

2、单选题：
​ If the bending moment M on the beam segment is a linear function of x, the function of shear force is (     ).‏
选项：
A: Constant;
B: Linear function;
C: Quadratic function;
D: 0.
答案: 【 Constant;】

3、单选题：
‎For plane bending the characteristics of deformation are (    ).‌
选项：
A: The cross section remains plane when bent;
B: The axis after deformation is a plane curve;
C: All external loads act on the same plane;
D: The axis after deformation is in the same plane with the loading plane.
答案: 【 The axis after deformation is in the same plane with the loading plane.】

4、单选题：

‎As shown in the figure, the cantilever beam is subjected to a uniformly distributed load. In the following conclusions, (   ) is wrong.

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‎

‏选项：
A: The shear force of each cross section is greater than or equal to zero;
B: The shear force in segment AB is constant;
C: The bending moment of each cross section is less than or equal to zero;
D: The bending moment in segment AB is constant.
答案: 【 The bending moment in segment AB is constant.】

5、单选题：

‎The cantilever beam and the simply supported beam are equal in length, they have (     ).

​

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​选项：
A: Different bending moment diagrams and the same shear force diagrams;
B: The same bending moment diagrams and different shear force diagrams;
C: The same bending moment diagrams and the same shear force diagrams;
D: Different bending moment diagrams and different shear force diagrams.
答案: 【 The same bending moment diagrams and the same shear force diagrams;】

Chapter 11 Stresses in Bending

1、单选题：
‏In the following cases, (    ) belongs to pure bending.‌
选项：
A: The external loads act on the longitudinal symmetric plane of the member;
B: The members are only bent without torsion and tension deformation;
C: The load on the member is only concentrated couples;
D: There is no shear force on each cross section of the member, and the bending moment is a constant.
答案: 【 There is no shear force on each cross section of the member, and the bending moment is a constant.】

2、单选题：

‌The forces on the cantilever beam are shown in the figure, (       ).

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‌

‍选项：
A: Pure bending occurs in segment AB and transverse bending occurs in segment BC;
B: The beam is in pure bending;
C: Pure bending occurs in segment BC and transverse bending occurs in segment AB;
D: The beam is in transverse bending.
答案: 【 Pure bending occurs in segment AB and transverse bending occurs in segment BC;】

3、单选题：

‌The cantilever beam with T-section subjected the force as shown in the figure, where   axis passes through the centroid of the cross section, which is (      ) of the cross section of the beam.

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‏选项：
A: The neutral axis is  axis, and the maximum tensile stress is at the upper edge of the beam;

B: The neutral axis is  axis, and the maximum tensile stress is at the lower edge of the beam;

C: The neutral axis is  axis, and the maximum tensile stress is at the upper edge of the beam;

D: The neutral axis is  axis,