Chapter 1 Introduction Chapter 1 Introduction Getting pI repared! Measurement Models Theories and laws Vector and scalar
Chapter 1 Introduction Getting prepared!!! Chapter 1. Introduction • Measurement, Models, Theories and Laws • Vector and Scalar
Chapter 1 Introduction 1-1 Models, theories, and laws(P3) Model: is a kind of mental image of the phenomena in terms of something are familiar with Theory: is broader, more detailed, and attempts to solve a set of phenomena Law: are general statements about how nature behaves. The statement takes the form of a relationship or equation(方程) between quantities(量)
Chapter 1 Introduction 1-1 Models, theories, and laws (P3) Model: is a kind of mental image of the phenomena in terms of something are familiar with. Theory: is broader, more detailed, and attempts to solve a set of phenomena. Law: are general statements about how nature behaves. The statement takes the form of a relationship or equation ( 方 程 ) between quantities (量)
Chapter 1 Introduction 1-2 Measurement and Uncertainty; Significant Figures(P3-5) Physics is based on measurement of physical quantities(物理量,P3 Significant Figures(有效数字): The number of relia bly known digits in a number is called the number of significant figures P4
Chapter 1 Introduction 1-2 Measurement and Uncertainty; Significant Figures(P3-5) Physics is based on measurement of physical quantities (物理量). P3 Significant Figures(有效数字): The number of reliably known digits in a number is called the number of significant figures. P4
Chapter 1 Introduction Scientific notation(科学记数法(p4) Write numbers in“ powers of ten” Mass of the earth: 5,980,000,0000000kg or 5.98x1044kg Diameter of proton(质子) 0.000000000000001m or 10-15m(or 1 E-15 on computers) The advantage is that it allows the number of significant figures to be clearly expressed
Chapter 1 Introduction Mass of the Earth: 5,980,000,000,000,000,000,000,000kg or 5.98x1024kg Diameter of proton（质子）: 0.000000000000001m or 10-15m (or 1 E-15 on computers) The advantage is that it allows the number of significant figures to be clearly expressed. Scientific notation (科学记数法(p4) Write numbers in “powers of ten
Chapter 1 Introduction 1-4 Units, Standards, and the sI System(P5-7) Unit(单位 We measure each physical quantity in its own units(单位) by comparison with a standard.Ps SI System(国际单位制): There are so many physical quantities that it is a problem to organize them. Fortunately, they are not all independent(独立).P7
Chapter 1 Introduction 1-4 Units, Standards, and the SI System (P5-7) Unit (单位): We measure each physical quantity in its own units(单位) by comparison with a standard. P5 SI System (国际单位制): There are so many physical quantities that it is a problem to organize them. Fortunately, they are not all independent （独立）. P7