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Answer to 10th and 11th Grade Physics Problems - Inertia and Newton's First Law
Review Questions for Dynamics/Forces Unit

Standing Wave Model is shown here:   http://www.phy.ntnu.edu.tw/ntnujava/viewtopic.php?t=35   (blue represents the incident wave, the black represents the reflected wave and the red represents the resultant standing wave)

Link for Coefficient accepted values   http://hypertextbook.com/physics/mechanics/friction/