Question

Self adjusting force

Answer 1

In this sense the normal force adjusts itself. Other examples of forces that behave this way are static friction and the tension in a rope or cord. The magnitude of static friction adjust its value to the applied force hence static friction is called selfadjustable.

Friction (like friction drag) is a contact force which results from two surfaces contacting each other. Static friction is considered a self adjusting force because it wants to the objects to remain at rest and not move. Therefore, if an external force is applied, the static friction force will equal the magnitude of the external force, until it surpasses the threshold of motion. At this point, static friction becomes kinetic friction and the object begins to move.



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