The Free High School Science Texts: A Textbook for High School Students Studying Physics.
August 5, 2005
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Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
Next section: Chapter 2: Waves and Wavelike Motion