| 释义 |
DictionarySeeequationequation of motion
equation of motion[i′kwā·zhən əv ′mō·shən] (fluid mechanics) One of a set of hydrodynamical equations representing the application of Newton's second law of motion to a fluid system; the total acceleration on an individual fluid particle is equated to the sum of the forces acting on the particle within the fluid. (mechanics) Equation which specifies the coordinates of particles as functions of time. A differential equation, or one of several such equations, from which the coordinates of particles as functions of time can be obtained if the initial positions and velocities of the particles are known. (quantum mechanics) A differential equation which enables one to predict the statistical distribution of the results of any measurement upon a system at any time if the initial dynamical state of the system is known. equation of motion
e·qua·tion of mo·tion (ĕ-kwā'zhŭn mō'shŭn) 1. An expression of Newton's second law that relates forces, displacements, and their derivatives for a mechanical system. 2. For the respiratory system, an equation that relates the forces involved in breathing to the displacements they produce. Typically, pressure differences are used to represent generalized forces and volume changes are used to represent generalized displacements. The simplest equation of motion written for the lungs states that the change in transpulmonary pressure is equal to the sum of an elastic term plus a flow resistive term: transpulmonary pressure change = elastance × tidal volume + resistance × change in flow. equation of motionA statement of the variables of pressure, volume, compliance, resistance, and flow for respiratory system mechanics. See also: equation |