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Homework Help: Velocity expression

  1. Sep 25, 2005 #1

    ytsejam

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    hi this is first time for me here and it seems very useful.

    my question is:

    the expression is velocity of object while t->infinity

    the object will stop somewhere in time? and if it will , when

    i think it will go on forever. but i'm not sure


    thanks

    liron
     

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    ytsejam, Sep 25, 2005
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  3. Sep 25, 2005 #2

    LeonhardEuler

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    A good way to look at it is to remember that [tex]e^{-x}=\frac{1}{e^x}[/tex], so
    [tex]V(t)=\frac{v_0}{e^{t/x}}[/tex]
    Now it should be clear what happens as time approaches infinity. Keep in mind, though that approaching a number is something different from reaching it.
     
    LeonhardEuler, Sep 25, 2005
  4. Sep 25, 2005 #3

    ytsejam

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    correction

    correction...my fault in the paste.
    the x supposed to be taw-time constant.

    it is change your asseveration?


    thanks
     
    ytsejam, Sep 25, 2005
  5. Sep 25, 2005 #4

    LeonhardEuler

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    That really doesn't change anything, now it is just:
    [tex]V(t)=\frac{v_0}{e^{t/\tau}}[/tex]
     
    LeonhardEuler, Sep 25, 2005
  6. Sep 25, 2005 #5

    ytsejam

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    so it will stop?
     
    ytsejam, Sep 25, 2005
  7. Sep 25, 2005 #6

    LeonhardEuler

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    As time approaches infinity the speed will get closer and closer to zero, but not reach it. It will move so slowly that it will not travel an infinite distance, it will just get closer and closer to some point, going more and more slowly and never getting there.
     
    LeonhardEuler, Sep 25, 2005
  8. Sep 25, 2005 #7

    ytsejam

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    ...what i thought.

    thanks for clearing it for me
     
    ytsejam, Sep 25, 2005
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