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Homework Help: Basic formulas for motion

  1. Nov 12, 2007 #1
    I have no idea if this is the right forum but I am doing the kinematics chapter in 2204 and I was wondering if anyone had the bassic forumlas for motion.
    Last edited: Nov 12, 2007
  2. jcsd
  3. Nov 12, 2007 #2
    Yea, try :

    V = u+at

    (V^2) = (u^2) + 2as

    s = ut + 0.5a(t^2)


    u = initial velocity
    v = final velocity
    s = distance (or more correctly displacement)
    a = acceleration
    t = time
  4. Nov 12, 2007 #3
    In my corse we use V1 and V2, D is Displacement, Is this like V1= U, V2=V and D=S?
    Last edited: Nov 12, 2007
  5. Nov 12, 2007 #4
    The given information to the simple problem I am trying to complete is V1=10, A=1, V2= 15 and D=?. I just lost my formula sheet and I am lost.
  6. Nov 12, 2007 #5
    Yea its same thing as you've put there, and as for the first question you would use,

    (v2^2) = (v1^2)+2ad

    and rearrange for d
  7. Nov 12, 2007 #6
    So to rearrange for D would you use D= (V1^2) + 2a over (V2^2)? I used that and ended up with 0.4 for my answer, I don't believe thats correct?
  8. Nov 12, 2007 #7
    This is all in Meters per second also.
  9. Nov 12, 2007 #8
    Nope thats wrong, rearrange it in these steps :

    (v2^2) = (v1^2)+2ad

    You wanna clear everything off the right hand side to leave d on its own, so start by moving (v1^2) :

    (v2^2) - (v1^2) =2ad

    And now divide both sides by 2a, and so :

    (v2^2) -(v1^2) = 2ad

    ((v2^2) -(v1^2))/2a = 2ad/2a

    to get :

    ((v2^2) -(v1^2))/2a = d

    As you can see the 2a on the right hand side cancels when you divide that side by 2a

    And yea everythign is in SI units so thats meters per second, meters, seconds etc
  10. Nov 12, 2007 #9
    OK I did that and came out with 125 m/s which I think looks like it may be correct. But I'm not sure.
  11. Nov 12, 2007 #10
    Not quite, you only divided by a, when its supposed to be divide by 2*a
    And d is a distance so its measured in just m, m/s is for velocity
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