Διάδοση και ανάκλαση ήχου

http://www.acoustics.salford.ac.uk/schools/teacher/lesson3/flash/whiteboardcomplete.swf

http://www.ndt-ed.org/EducationResources/HighSchool/Sound/Graphics/Flash/multiroom.swf

http://www.acoustics.salford.ac.uk/schools/lesson3/lesson1p3.htm

http://static.howstuffworks.com/flash/bat-echo.swf και http://www.dolphinkind.com/images/echolocation.swf