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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