1. The problem statement, all variables and given/known data 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. 2. Relevant equations mu=Fs, max/Fnormal? 3. 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.