等效替换物理思想解决刚体定轴转动问题

Solving the Questions of Fixed Axis Rotation of Rigid Body with the Idea of Equivalent Replacement Physics

用等效替换的物理思想深刻理解和直观快速解决一类典型刚体定轴转动问题,并推广至刚体平面运动的非定轴转动问题.定轴转动问题的标准解法是隔离物体做受力分析,列方程组然后求解.但标准解法步骤繁复容易出错,另外解的过程主要依靠数学推导求解方程组,不利于理解问题的物理本质和意义.而使用等效替换思想解决这类问题时,把直线运动和定轴转动的复合运动转化为求解单一直线运动问题,或者转化为求解单一定轴转动问题,再将整个系统看成一体求解,从而极大简化了求解过程,并帮助更直观深刻地理解问题的物理本质和物理意义.

The physical thought of equivalent substitution was used to deeply understand and quickly solve a kind of typical fixed axis rotation problem of rigid body.It was extended to non-fixed axis rotation problems of linear rolling of rigid body moving in plane.The standard solution to the fixed-axis rotation problem is to isolate the object for force analysis,build the equations and solve them.However,the standard solution method is complex and error-prone,and the solution process mainly relies on mathematical derivation to solve the equations,the standard solution is not help to understanding the physical nature and significance of the problem.And when using the equivalent substitution thought to solve such problems,the compound movement in the linear motion and the fixed axis rotation is converted into solving the problem of a single linear motion,or converted to solve problems of single axis rotation,then the whole system as a whole solution,the equivalent substitution thought greatly simplifies the solving process,and help more intuitive to profoundly understand the physical nature of the problem and the physical meaning.