You can download a dos simulation which will do just that from my web page,
listed below. [It actually animates the sine and not the cosine.]
This is a truncated version of the 'Wave Interference" program put out by Physics
Academic Software.
Go to the Packets Page, then to Waves, and toward the bottom of the Waves
page is the download for this program.
--
Mike
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Mike Moloney moloney@nextwork.rose-hulman.edu
Dept of Physics & Applied Optics (812) 877 8302
Rose-Hulman Institute of Technology Terre Haute, IN 47803 http://www.rose-hulman.edu/~moloney