Raise the angle past tanθ = μ and the block breaks loose and slides
Driving mg·sinθ—
Normal N = mg·cosθ—
Max static friction μN—
Friction force f—
Net force—
Acceleration a—
Slip angle atan μ—
State—
Acceleration a = g(sinθ − μcosθ) versus ramp angle; the dashed line is the slip angle, the dot the current angle.