物理学 第五版 2-1牛顿定律 三牛顿第三定律( Newton third law) 作用与反作用定律( Law of action& reaction) 两个物体之间作用力F12和反作用力F21,沿同 直线,大小相等,方向相反,分别作用在两个物体上 The active force(action) Fn and the reactive force(reaction F2l between two objects act upon each object, respectively, and the forces are equal in magnitude, opposite in direction, and along the same straight line ★F=-F 12 21 (物体间相互作用规律) The interactive law between objects 第二章牛顿定律 9/16第二章 牛顿定律 物理学 第五版 2-1 牛顿定律 9/16 两个物体之间作用力F12和反作用力F21 , 沿同一 直线, 大小相等, 方向相反,分别作用 在两个物体上 . F12 F21     (物体间相互作用规律) 三牛顿第三定律(Newton third law) 作用与反作用定律(Law of action & reaction) F21  F12  The active force(action) F12 and the reactive force(reaction) F21 between two objects act upon each object, respectively, and the forces are equal in magnitude, opposite in direction, and along the same straight line The interactive law between objects