Question:
why can't the coefficient of friction equal more than one?
Replies:
The coefficient of friction CAN be more than one.
Friction is a force relating to molecular structure of two surfaces
touching each other. Molecules from one surface link with molecules from
the other. If you press the objects together more tightly, you push the
surfaces closer together, joining more molecules. This is why friction is
proportional to the "normal force", how tightly the surfaces have to push on
each other to keep from breaking. This proportion is the coefficient of
friction.
Molecules on adjoining surfaces just don't cling to each other strongly
enough to have a huge friction coefficient. Solid molecules prefer to cling
to each other rather than other solid materials. This is pretty much what
makes them solid. In theory, there may be some solid materials that cling
to each other strongly enough to have a huge coefficient of friction. I
just don't know of any.
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