CMD 278 Lecture Notes - Lecture 5: Ambient Pressure, Rubber Band, Tuning Fork
11 Oct 2016
School
Department
Course
Professor
Document Summary
Lecture 5 acoustics: a physical event disturbance of particles in a medium, there are 3 necessary components for sound production. Sounds: waves of tiny fluctuations in air pressure that propagate (radiate) from the source. Pressure changes from sound waves= localized disturbances from ambient air pressure. Air = most common propagating medium for sound. Consists of billion of molecules: these molecules are spaced consistently in regard to their distance from one another, mass, elasticity, inertia. Mass = any form of matter (solid, liquid, gas) air particles consist of mass. Gravity acts as a force when the weight is dropped, the weight causes the rubber band to move up and down. Resistance dissipates energy in a system by converting energy into thermal energy (heat) Mass, stiffness, and resistance constitute impedance (overall opposition to energy transfer) in a mechanical system. The dissipation of vibratory energy is called damping.
