PSYC 100 Study Guide - Midterm Guide: Middle Ear, Sine Wave, Sound

• School: Queen's University
• Department: Psychology
• Course: PSYC 100
• Professor: Jordan Poppenk

Document Summary

Whatever is emitting a sound vibrates, this vibration causes adjacent air molecules to become compressed into local regions of increased pressure, and rarefied in local regions of decreased pressure. Sound waves have amplitude and wavelength (like light waves) Amplitude of a sound wave determines the sound"s intensity. For sound, rather than intensity, it"s called frequency (which is directly calculated from the wavelength) Most sounds consist of many different frequencies (shown in a spectrum) Wavelength is the distance the sound travels in one cycle (or period) The longer the period, the longer the wavelength and the lower the frequency. Number of cycles (number of periods) between high and low pressure in one second stated in units called hertz (hz). If one compression and one rarefaction occur within exactly one second, then the frequency of that sound equals 1 cycle/ second or 1 hz. The frequency of sound is related to our perception of pitch.