20.1 The magnetic field and its application 1. The magnetic field and its features Gravitational field FG=mg -gravitational force caused by mass Electric field =gE -electric force caused by electric charge Magnetic field--? While the magnetic field has similarities to the other fields, it also has some unique features that distinguish it from the others
The dynamics of many-particle systems is called statistical mechanics. The kinetic theory is a special aspect of the statistical mechanics of large number of particles. Suitable averages of the physical characteristics and motions of individual particles provide information about the macroscopic behavior of the system as a whole
I．Choose the Correct Answer 1. A disturbance can be written x b xt b t a y(x,t) (e e e ) 2 2 −( / ) 2 / − = . This disturbance is （ D ） (A) Not a traveling wave. (B) A traveling wave with speed v = a. (C) A traveling wave with speed v = a/b. (D) A traveling wave with speed v = b
4.1 卤代烃的分类 结构和命名 Classification, Structure, and Nomenclature of Alkyl Halides 4.2 卤代烃的物理性质 Physical Properties of Alkyl Halides 4.3 卤代烃的化学性质 Chemical properties of Alkyl Halides
第一节 土的形成 1.1 The Formation of soils 第二节 土的三相组成 1.2 The Three-Phase Composition of soils 第三节 土的物理状态 1.3 The Physical State of Soils 第四节 土的结构 1.4 The structure of soils 第五节 土的工程分类 1.5The engineering classification of soils 第六节 土的压实性 1.6 Soil Compaction
7.1 芳香烃的分类 结构及命名 Classification, Structures and Nomenclature of Aromatic Compounds 7.2 芳香烃的来源及物理性质 Sources and Physical Properties of Aromatic Hydrocarbons
