APA 2114 Lecture Notes - Lecture 16: Angular Velocity, Conservative Force, Resultant Force
15 Oct 2018
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Document Summary
Power: power is the rate of work production, also defined as the rate at which energy is expended, measured in watts. Power of force: the product of the instantaneous force and the velocity of the body that the force is acting upon. Power of a moment ( moment of force: the product of the instantaneous moment and the angular velocity of the body that the moment is acting upon. Conservation of mechanical energy: only occurs under special circumstances, decrease in one energy type leads to an increase in another, when the resultant force acting on a body is a conservative force. Non- conservative forces: dry friction, dependant on path, normal force and surfaces, vicious forces, dependant on velocity, surface area, muscle forces, dependant on excitation, strength, viscoelastic forces, muscles, ligaments, tendons, air (fluid) resistance, plastic collisions. Issues arise when the cyclic movement patterns zero-work paradox: mechanical work is done but there is no external work.
