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What is a self adjusting force? I searched it everywhere on internet but not got my answer and I have no other source to get its answer except this site so please help me.

Qmechanic
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    In what context? – John Alexiou Feb 24 '15 at 18:42
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    In criteria of Kinematics. –  Feb 24 '15 at 18:42
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    I dont think it is standard term. It could mean a force that is a function of position, but it sure is an obtuse way of stating this. – John Alexiou Feb 24 '15 at 18:50
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    I suspect that OP is talking about support forces and static friction: forces that take on a value that prevents [some behavior] or insures [other behavior]. That said, I don't recall seeing that term used to describe them in the past, even though I may steal the idea of using the phrase "self-adjusting" for the next time I teach intro mechanics. – dmckee --- ex-moderator kitten Feb 24 '15 at 19:56

2 Answers2

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Assuming the interpretation I suggested in the comments is correct.

Consider the normal support force.

It is an expression of the solidity of the surface that won't allow interpenetration. In order for penetration to not happen, there must be a force to prevent the supported object from accelerating toward the surface. Ultimately the origin of this behavior is found in inter-molecular forces, but at the macroscopic scale it's character is that it automatically takes on exactly the value need to prevent interpenetration without hurling the object off the surface (at least until the surface start to deform significantly or undergoes catastrophic failure).

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.

dmckee --- ex-moderator kitten
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The magnitude of static friction adjust its value to the applied force hence static friction is called self adjustable....

Kyle Kanos
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Chandan G A
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  • Hi Chandan G A and welcome to Physics.SE! This is really a comment, not an answer. For this reason I'm flagging this post for deletion. With a bit more rep, you will be able to post comments. – Gonenc Aug 20 '15 at 14:27
  • Static friction will adjust to the applied force only up to a point, once the applied force exceeds the maximal value then it will allow movement (otherwise we'd never move anything!). – Kyle Kanos Aug 20 '15 at 14:35