Even surfaces that look perfectly smooth — like glass or polished steel — have a large number of microscopic bumps and pits.  What does this fact imply about friction?
AFriction has nothing to do with the smoothness of surfaces
BFriction can be reduced, but never entirely eliminated, since no real surface is perfectly smooth
CFriction is greater on smooth surfaces than rough ones
DFriction can be made exactly zero by polishing surfaces enough
Answer & Solution
Correct answer: B. Friction can be reduced, but never entirely eliminated, since no real surface is perfectly smooth
Polishing reduces the size and number of irregularities but cannot make them disappear at the microscopic level. Lubricants help further by separating the surfaces. But some friction always remains — the chapter states friction can never be entirely eliminated.
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