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. An object moves in the xy plane with an acceleration that has a positive x component. At time=0 the object has a velocity given by=3i +0j. What can be concluded about the y component of the acceleration?
I. Choose the Correct Answer 1. Which of the following quantities are independent of the choice of inertial frame? (There may be more than one correct answer) (A)Velocity (B)Acceleration (C)Force (D)Work Solution: In all the inertial frame, the forces acted on a body are same,=ma=F'=ma', therefore the force and acceleration are independent of the choice of inertial frame
2.1 scalar and vector quantities 1. scalar Physical concepts that require only one numerical quantity for their complete specification are scalar quantities. 2. vector Vector quantities require for their complete specification a positive quantity, called the magnitude of the vector and the direction otice:Not all things with a magnitude and direction are vectors
2.1 Plane stress and plane strain 平面应力问题与平面应变问题 2.2 Differential equations of equilibrium 平衡微分方程 2.3 Stress at a point. Principal stresses 一点的应力，主应力 2.4 Geometrical equations. Rigid-body displacements 一几何方程，刚体位移 Shear stress trajectories in a cantilever beam 悬臂梁的剪应力轨迹线 2.6 Physical equations. 物理方程 2.7 Boundary conditions 边界条件 2.8 Saint-venant`s principle-1 圣维南原理 2.9 solution of plane problem in terms of displacements 按位移求解平面问题 2.10 solution of plane problem in terms of stresses 按应力求解 2.11 Case of constant body forces 常体力情况 2.12 Airy`s stress function. Inverse method and semi-inverse method 艾瑞应力函数，逆解法，半 逆解法
