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Re: Banked road



At 11:48 AM 11/4/01 -0500, Ludwik Kowalski wrote:
The normal force with which an inclined plane is acting on an
object is N= m*g*cosA, where A is the angle of inclination.
Students use this approach to calculate accelerations (with or
without friction) or to solve equilibrium problems.

But in dealing with banked roads they are suddenly asked to
accept that N=mg/cosA. How can this be explained?

We are told "the same equations have the same solutions" but why should we
expect that radically different equations should lead to the same solutions?

Why do we have one formula for resistors in series and another for
resistors in parallel?

Why do we have one formula for first-class levers and another for
third-class levers?

Given two quantities A=5 and B=8, why is B 60% larger than A, while A is
only 37.5% smaller than B? Shouldn't it be the same percentage?