Static Friction: Max Force Magnitude Applied?

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celiachu
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Homework Statement



Which of the following statements are true about Fs, max in the equation mu=Fs, max/Fnormal?

I. Fs, max is exerted perpendicular to the surfaces in contact.
II. Fs, max represents the maximum value of the force of static friction.
III. On a level surface, the magnitude of the Fs, max equals the magnitude of the applied force that starts the object moving.

Homework Equations



mu=Fs, max/Fnormal?

The Attempt at a Solution



Well, I know that Friction is parallel to the surface and opposite to the direction of the force on the object, so I is out of the picture, and II seems a bit obvious, so that's one true answer. I'm not understanding the third one, though. Help? I just need an explanation to III to know if it is true or false.
 
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The maximum static friction will be at the instant just before the object starts to move. For example, if
[tex]F_{S, max}=12.000000000[/tex], then I would assume [tex]F=12.000000001[/tex] would be suffice to induce movement, which is essentially 12.