PSYC 4365 Lecture Notes - Lecture 23: Logarithmic Scale, Musical Tone, Sine Wave
Document Summary
Impairments of hearing and how to ameliorate them. What is sound: sounds are created when objects vibrate. Vibrations of an object cause molecules in the object"s surrounding medium to vibrate as well, which causes pressure changes in the medium. Figure 9. 1 pattern of pressure fluctuations of a sound stays the same as the sound wave moves away (a); amount of pressure change decreases with increasing distance (b: sound waves travel at a particular speed. Example: speed of sound through air is about 340 meters/second, but speed of sound through water is 1500 meters/second: physical qualities of sound waves: Amplitude or intensity: the magnitude of displacement (increase or decrease) of a sound pressure wave. Frequency: for sound, the number of times per second that a pattern of pressure change repeats: units for measuring sound: Hertz (hz): a unit of measure for frequency. Decibel (db): a unit of measure for the physical intensity of sound.
