功学 三、摩擦角: ①定义:当摩擦力达到最大值F。时其全反力 与法线的夹角φm叫做摩擦角。 om ②计算: IFm N 921 f R m NN 翻页请看动画 16
16 Fmax m 三、摩擦角： ①定义：当摩擦力达到最大值 时其全反力 与法线的夹角 叫做摩擦角。 翻 页 请 看 动 画 f N f N N F m = = = max tg ②计算：
Statics MMGR 0m R
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学 MMGR 0m R
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Statics 4. Self-locking (Concept: a body can be at rest by the mutual action of the force of friction and the normal pressure(l e, Total Reaction Force), it will not slide(no matter how great an applied force is), this phenomenon is called self-locking @2@Conditions of self-locking When a<p m the system is al ways in op equilibrium(I.e, it is self-locking) PLEx fim N R 19
19 4. Self-locking ①Concept: A body can be at rest by the mutual action of the force of friction and the normal pressure(I.e., Total Reaction Force), it will not slide (no matter how great an applied force is), this phenomenon is called self-locking. When the system is always in equilibrium (I.e., it is self-locking). m m ②Conditions of self-locking:
功学 四、自锁 ①定义:当物体依靠接触面间的相互作用的摩擦力与正 压力(即全反力),自己把自己卡紧,不会松开 (无论外力多大),这种现象称为自锁。 ②自锁条件 当<⑨m时,永远平衡(即自锁) o n PLEx fim N R 20
20 四、自锁 ①定义：当物体依靠接触面间的相互作用的摩擦 力 与正 压力（即全反力），自己把自己卡 紧，不会松开 （无论外力多大），这种现象称为自锁。 当 时，永远平衡（即自锁） m m ②自锁条件：