http://www.ilsitodi.it/laboratoriodifisica/attrito%20statico/scivolo.html
Static friction is friction between two or more solid objects that are not moving relative to each other. The static friction force must be overcome by an applied force before theobject is able to move.
The static coefficient of friction is measured on an inclined plane. This incline is increased (slider h) until the brick begins to slide. At this point, the inclined plane is locked and the angle can be read. The tangent of this angle is the coefficient of friction:
μs=h/l
