Question

what is self adjusting friction?

Answer 1

Static friction is called self adjusting friction.
It is called so because the static friction adjusts itself to provide an equal and opposite force to the applied external force as long as the external force is less than or equal to the maximum static friction.

For example, Let the maximum static friction is 20N.
If we apply a force 5N, the static friction will be 5N. If we change the applied force to 10N, then the friction will adjust itself and it will become 10N.

Answer 2

Static friction is known as self adjusting friction. Static friction is the friction which comes into play when surfaces of the objects are at rest relative to each other. For example:push a heavy box which is kept on a floor with a small force to move horizontally. The box doesn't move because there is a frictional force which is equal and opposite to the applied force on box.Now gradually increase the applied force, the box still doesn't move, because the frictional force also increases accordingly and balances the increased applied force. So we can say static friction is self adjusting friction. Hope this helps you