文档介绍：Chapter 3 : General Coplanar Force System
Theoretical Mechanics
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第三章平面一般力系
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Statics
Chapter 3: General Coplanar Force System
General coplanar force system: Several forces act on a body, the lines of action of these forces are in a plane, but they don’t intersect at one point and are not parallel.
[Example]
Reduction of a force system to a given point: Reduce an unknown force system(a general coplanar force system) to a known force system(a coplanar system of concurrent forces and a coplanar system of force couples)
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静力学
第三章平面任意力系
平面任意力系:各力的作用线在同一平面内,既不汇交为一点又不相互平行的力系叫∼。
[例]
力系向一点简化:把未知力系(平面任意力系)变成已知
力系(平面汇交力系和平面力偶系)
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Chapter 3: General Coplanar Force System
§3–1 Theorem of translation of a force
§3–2 Reduction of a general coplanar force system
to a given point
§3–3 Result of reduction of a general coplanar
force system • the law of the resultant moment
§3–4 Conditions and equations for the equilibrium of
a general coplanar force system
§3–5 equilibrium equations of a coplanar system of
parallel forces
§3–6 The concepts of statically determinate and statically indeterminate problems • the equilibrium of a body system
§3–7 Analysis of internal force of simple plane truss
Exercises
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第三章平面一般力系
§3–1 力线平移定理
§3–2 平面一般力系向一点简化
§3–3 平面一般力系的简化结果•合力矩定理
§3–4 平面一般力系的平衡条件和平衡方程
§3–5 平面平行力系的平衡方程
§3–6 静定与静不定问题的概念•物体系统的平衡
§3–7 平面简单桁架的内力分析
平面一般力系习题课
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§3-1 Theorem of translation of a force
Theorem of translation of a force: A force acting on a rigid body can be moved parallel to its lines of action to any point of the body, if we add a couple with a moment equal to the moment of the force about the point to which it is translated.
[proof]
force system force force system
Statics
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静力学
§3-1 力线平移定理
力的平移定理:可以把作用在刚体上点A的力平行移到任一
点B,但必须同时附加一个力偶。这个力偶
的矩等于原来的力对新作用点B的矩。
[证] 力力系
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①The theorem of translation of a force gives a relationship
between the force and force couple: force force+force
couple.
②The condition of translation of