[vahid]

4-comprehensive	3-experiments	2-principles	1-coulomb friction
8-sufficient	7-analytical	6-describe	5- theory
12-adjacent	11-fluid friction	10-majority	9-handle
16-viscosity	15-gradient	14-locity	13-velocity
20-internal friction	19-further	18-shearing	17-resistance
24-elastic  materials	23-cyclical	22-materials	21-occurs
28-appreciable	27-undergo	26-due	25-deformation
32-associated	31-mechanism	30-accompany	29-considerable
36-primarily	35-science	34-deals	33-shear
40-rigid	39-exterior	38-remainder	37-dry friction
44-experiment	43-simple	42-aid	41-explain
48-assume	47-horizontal	46-resting	45-consider
52-increase	51-continuously	50-application	49-roughness
56-diagram	55-velocity	54-appreciable	53-sufficient
60-always	59-labeled	58-exerted	57-tangential
64-resultant	63-toward	62-tendency	61-oppose motion
68-visualize	67-mating surface	66-irregularities	65-magnified
72-reaction	71-humps	70-intermittent	69-necessarily
76-deformation	75-local	74-extent	73-geometric
80-required	79-maintain	78-observation	77-components
84-as long as	83-equilibrium	82-perform	81-mesh
88-block	87-satisfy	86-period	85-slip
92-remains	91-abruptly	90-slightly	89-applied
96-impending	95-slippage	94-region	93-static friction
100-equilibrium	99-equations	98-determined	97-range

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