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Many students in introductory physics courses believe that only active
forces exist. The following is a typical statement: "The table doesn't
exert a force on the falling ball: It simply gets in the way." Physics
education research has shown that addressing this preconception helps
many of these students to better understand normal force, tension and
other passive forces.
We agree that this misconception exists. We agree that addressing it is
helpful.
Tangential remark: I see this misconception as one element of a large
bundle of misconceptions. Other elements include the pre-Galilean
notion that objects at rest remain at rest, and objects in motion tend
to come to rest.
It is also connected to innumerable problems with the terminology.
When it comes to the table "getting in the way", there are at least
two ways of explaining the situation to students:
a) Explain it in terms of a force of constraint. Explain that
in terms of Hooke's law, using a large spring constant k and
a small deflection x. This is easier to visualize if you replace
the tabletop with a not-very-taut rubbery drumhead, as discussed
at http://www.av8n.com/physics/causation.htm