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Is every mechanical process or mechanical reversible?

  1. Mar 17, 2008 #1
    Is evry mechanical process or mechanism reversiible?
    By that i mean to say, Can we carry out every mechanism or process in reverse?

    for eg: if i have a mechanism which converts rotary motion to oscillatory, can i use the same mechanism for changing the oscillatory motion to rotary, without making any modification in the mechanism?
  2. jcsd
  3. Mar 18, 2008 #2


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    Welcome to PF.
    The short answer is 'no'.
    The simplest example might be a worm drive. That would be the same as a lead-screw (screw jack in some terminologies). It is absolutely not reversible. That's why they're used for things like automotive jacks.
  4. Mar 18, 2008 #3


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    I can think of MANY mechanisms off the top of my head which can't be run in reverse. I can also think of many mechnisms which are very efficient in one direction, and very inefficient in the opposite direction.
  5. Mar 19, 2008 #4
    at least when i think of friction, i must say most of the mechanical processes are not reversible. One lose mechanical energy during the process. Perhaps... you are trying to mean... something else?
  6. Mar 19, 2008 #5
    A falling brick is a mechanical system! Almost any process has a preferred direction and thermodynamically speaking there is no such thing as a reversible process in real life.
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