The superstar Erya learned the answer to the exam in Chapter 2023 of Engineering Mechanics (Huazhong University of Science and Technology).
1.6 chapter test
1, about the role of force, the following statement is the most accurate ()?
A, the role of force is to make the object move.
B, the role of force is to make the position of the whole object change with time, which is called motion.
C, the role of force is to change the size and shape of the object itself, which is called deformation.
D, there are two kinds of force, one is the change of the position of the whole object with time, called movement; The other is the change of the size and shape of the object itself, which is called deformation.
Correct answer: D.
2, the relationship between force and motion, the following statement is the most accurate ()?
A, the change of the object's motion state (dv/dt=a) is directly proportional to the force acting on it, which occurs on the line of force, that is, F=ma.
B, motion has nothing to do with force.
C, strong sports, sports is strong.
D, the force is proportional to the motion.
Correct answer: a
3, the relationship between force and deformation, the following statement is the most accurate ()?
A, the force is proportional to the deformation, and the deformation is strong.
B force and deformation satisfy Hooke's law
C, the relationship between force and deformation is related to the properties of materials.
D, the force is too small, the object is not deformed.
Correct answer: C.
4, about the balance of objects, the following statement is the most accurate ()?
Balance is when an object is at rest.
B, the motion speed of zero objects is balanced.
C, the balance of the object has nothing to do with the movement of the object.
D, the motion state of the object is in a state of balance and does not change.
Correct answer: D.
5, about the research content of engineering mechanics, the following statement is the most accurate ()?
First, engineering mechanics only needs to study the force of objects.
B, engineering mechanics only need to study the deformation of objects.
C, engineering mechanics only need to study the relationship between stress and deformation of objects.
D, engineering mechanics needs to study the force, motion and deformation of objects, and the relationship between force and motion or deformation.
Correct answer: D.
6. Engineering mechanics is a basic science, which studies the universal laws of natural science. At the same time, engineering mechanics faces and serves engineering, and it is also a technical science with dual attributes of basic science and technical science.
Correct answer:
7. Engineering mechanics is a classic Newtonian mechanics.
Correct answer: X.
8. The purpose of engineering mechanics is to understand the behavior of engineering systems and provide reasonable rules for their design.
Correct answer:
9. The interaction between objects is always equal in size and direction, and acts on different objects.
Correct answer: X.
10, the direct contact force between objects is surface force, and the indirect contact force is volume force.
Correct answer:
2.6 chapter test
1, for the plane force system in the figure, try to judge whether the listed equilibrium equation is necessary and sufficient ()?
A, (1), (2) and (3) are necessary and sufficient, while others are insufficient.
B, (2), (3) and (4) are necessary and sufficient, and the rest are insufficient.
C, (1) (4) and (5) are necessary and sufficient, and the rest are insufficient.
D, (2), (4) and (6) are necessary and sufficient, while others are insufficient.
Correct answer: b
2. Find the resultant force FR () acting on the bracket in the figure?
a、FR=600kN
B, FR = 247.9kN
C, FR=247.9kN, =6.2 (third quadrant)
D, FR=247.9kN, =6.2 (second quadrant)
Correct answer: D.
3. Find the resultant force FR () of the intersecting force systems in the graph?
A, fr =1.115kn, =67.55 (third quadrant)
b、FR= 1 1 1.5kN
C, fr =1.115kn, =6.2 (third quadrant)
D, fr =111.5kn, =6.2 (second quadrant)
Correct answer: a
4. The action of two forces is shown in the figure, f1= 500 n. In order to lift the stake, the vertical resultant force FR should be 750 N, and the F2 force should be as small as possible. Try to find the size and angle of F2 ().