Properties+of+waves

=Properties of waves=

oscillation-
pictures; http://www.google.com.au/search?q=what+is+the+trough+in+a+sound+wave&um=1&hl=en&client=safari&sa=N&rls=en&tbm=isch&tbs=simg:CAESEgnLfZNOr_1J1liHEaOrZe6zexg&iact=hc&vpx=177&vpy=98&dur=2343&hovh=185&hovw=272&tx=30&ty=278&ei=xbwvTo-_COHYiAKN0ukr&page=1&tbnh=126&tbnw=185&ved=1t:722,r:0,s:0&biw=1242&bih=666

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