Skill 4 of 10
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Kinetic friction models

Friction is not only due to ‘“peaks” sinking into “valleys”’. The two touching surfaces are rough, so their “peaks”, or asperities, are touching. When touching, they bond as with “glue” to each other. Some bond weakly, some bond strongly, depending on materials (and various chemical factors). We must break all of these bonds to make the surfaces slide.[1] This is kinetic friction.

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  1. Why is static friction greater than kinetic friction?’ (web page), Danielle Collins, Motion Control Tips, 2019, www.motioncontroltips.com/why-is-static-friction-greater-than-kinetic-friction (accessed Oct. 4th, 2019)
  2. Systematic breakdown of Amontons’ law of friction for an elastic object locally obeying Amontons’ law’ (article), Michio Otsuki & Hiroshi Matsukawa, Scientific Reports, vol. 3, article, 2013, DOI 10.1038/srep01586
  3. On the origin of Amonton’s friction law’ (article), B N J Persson, I M Sivebaek and others, Journal of Physics: Condensed Matter, vol. 20, issue 39, October 1, 2008, stacks.iop.org/0953-8984/20/i=39/a=395006?key=crossref.6d01fd5b96cc8a216cf034d5d25d3afa, DOI 10.1088/0953-8984/20/39/395006
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  5. Modeling and measuring friction effects’ (article), Avraham Harnoy, Bernard Friedland and others, IEEE Control Systems, vol. 28, issue 6, December 2009, www.researchgate.net/publication/224341110_Modeling_and_measuring_friction_effects, DOI 10.1109/MCS.2008.929546
  6. Encyclopædia Britannica’ (encyclopedia/dictionary), www.britannica.com
  7. Guillaume Amontons’ (article, in French), Jaime Wisniak, Revista CENIC Ciencias Químicas, issue 36, 2005, pages 187–195
  8. A model for friction in metal forming processes’ (article), Niels Bay & Tarras Wanheim, CIRP Annals: Manufacturing Technologies, vol. 27, 1978, www.researchgate.net/publication/279893157_A_model_for_friction_in_metal_forming_processes
  9. Sears and Zemansky’s Univesity Physics with Modern Physics’ (book), Hugh D. Young & Roger A. Freedman, Pearson Education, 13th ed., 2012
  10. Online Etymology Dictionary’ (dictionary), Douglas Harper, www.etymonline.com
  11. Modeling of Metal Forming and Machining Processes’ (book), Prakash Mahadeo Dixit & Uday S. Dixit, Springer London, 2008, books.google.dk/books?id=sg0GgoxI_qAC, ISBN 978-1-84800-188-6, DOI 10.1007/978-1-84800-189-3