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Homework Help: Basic Kinematic Equations

  1. Sep 9, 2010 #1
    I already typed a long drawn out post, so I am going to simplfy it.

    I am having trouble using algebra to rearrange equation.

    For Example,

    v=d/t
    And so, to solve for both t and d, I do the following

    vt=d/t x t
    vt=d
    vt/v=d/v
    t=d/v

    I have difficulty with most if not all the other equations. For example, the formula for acceleration.

    a=Vf-Vi/t
    Solve for t

    a=Vf-Vi/t
    at=Vf-Vi/t x t
    at + Vi=Vf -Vi + Vi
    at+Vi=Vf
    Vf-Vi/a=t

    This is my attempt at it. I multiplied by t, then eliminated the negative, and finally divided by a.

    Thank you ahead of time!
     
  2. jcsd
  3. Sep 9, 2010 #2

    rock.freak667

    User Avatar
    Homework Helper

    Yes those are correct.

    For the second one, you could have done it simpler instead of expanding out:

    a=(vf-vi)t

    multiplying both sides by 't'

    at=(vf-vi)

    divide both sides by 'a'

    t=(vf-vi)/a
     
  4. Sep 10, 2010 #3
    Thank you very much.

    Are there any tricks to rearranging equations? or rules to follow?
     
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