昆明理工大学：《大学物理》课程教学资源（PPT课件，英文版）第二章 动力学 Dynamics（Newton’s Laws of Motion）

Chapter2 Dynamics(动力学) (Newtons Laws of Motion) 总

Chapter 2 Dynamics(动力学） (Newton’s Laws of Motion)

2-1 Newton's laws force nertial Reference frame牛顿定律力的概念惯性参考系 82-2 General Properties of Forces in Mechanics 力的基本性质 82-3 The Fundamental Forces of Nature 四种基本力 82-4 Fundamental Quantities and Units Dimensions*基本量和力学单位制量纲 82-5 Applying Newton,s Law of Motion 牛顿定律应用

§2-1 Newton’s Laws Force Inertial Reference Frame 牛顿定律 力的概念 惯性参考系 §2-2 General Properties of Forces in Mechanics 力的基本性质 §2-4 Fundamental Quantities and Units Dimensions ﹡基本量和力学单位制 量纲 §2-5 Applying Newton’s Law of Motion 牛顿定律应用 §2-3 The Fundamental Forces of Nature ﹡ 四种基本力

教学要求 1.理解牛顿运动定律的内容及实质; 2掌握用隔离法解一般动力学问题;

教 学 要 求 1. 理解牛顿运动定律的内容及实质； 2.掌握用隔离法解一般动力学问题；

牛顿: Sir saac newton, 1643-1727,英国物理学家 数学家和天文学家,经典 物理学的创始人,科学史上 的巨人。 主要成就:(1)微积分;(2)牛顿三大定理(The Mathematical Principles of Natural Science);(3)JA 引力定理;(4)光学及他的光的‘微粒’学说( Optics); (5)反射式望远镜的发明;

牛顿： Sir Isaac Newton, 1643~1727,英国物理学家、 数学家和天文学家，经典 物理学的创始人,科学史上 的巨人。 主要成就： （1）微积分；（2）牛顿三大定理（The Mathematical Principles of Natural Science)；（3）万有 引力定理；（4）光学及他的光的‘微粒’学说(Optics)； （5）反射式望远镜的发明；

We will face the question: What leads to motion of a particle? causes particles effects forces mass Changes of motion Newton's third law first law state Relation?

We will face the question: What leads to motion of a particle? causes particles effects forces Newton’s third law mass first law Changes of motion state Relation?

Newton's second law F-

Newton’s second law F ma   =

Dynamics is to study the forces and their effects on the motions of obiects Ford 1913 In this chapter, we shall see that the cause of acceleration is a force exerted (使于) by some external(外部的) agent(力量) or environment(环境)

Dynamics is to study the forces and their effects on the motions of objects. In this chapter, we shall see that the cause of acceleration is a force exerted （使于） by some external（外部的） agent(力量） or environment（环境）

s2-1 Newton's Laws Force Inertial(惯性) Reference frame 1 Newton’ first law( The law of inertia惯性) A body at rest remains (te 持) rest and a body in motion continues to move at constant(但定) velocity unless acted upon by an external force(外力)

§2-1 Newton’s Laws Force Inertial（惯性）Reference Frame 1.Newton’ First Law （The Law of Inertia惯性） A body at rest remains（保 持 ） rest and a body in motion continues to move at constant（恒定） velocity unless acted upon by an external force（外力）

It should be noted: (1)An important property of all bodies- Inertia, the tendency(趋势) of bodies to maintain their original(原来的) state of motion. The force,not being the cause of motion of body, is the cause of change of motion of a body. D

⑴ An important property of all bodies — Inertia, the tendency（趋势） of bodies to maintain their original（原来的） state of motion. The force, not being the cause of motion of body, , is the cause of change of motion of a body. It should be noted:

(2)A qualitative definition of the concept of force as that which changes the state of motion Eon F2l The changes of their motions are same Conclusion (结论):F2>F1

⑵ A qualitative definition of the concept of force — as “that which changes the state of motion. F F The changes of their motions are same Conclusion（结论）: F  F