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Homework Help: Basic solution help

  1. Feb 2, 2006 #1
    Hi I am studying for this first physics test and having trouble.

    heres the eqation im using to find x and im sure its right but i can't seem to get the answer they do

    x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

    I am not getting the 77.5

    8 *5 = 40

    3.0 x 5.0 = 15

    15 * .5 = 7.5

    so 40 + 7.5 = 47.5

    I have a feeling that it has something to do with the time being squared buy my algebra sucks.. can someone explain this solution.
     
  2. jcsd
  3. Feb 2, 2006 #2
    the equation is [tex] x=\frac{1}{2}at^2+v_ot[/tex] you forgot to square the time when multiplying against acceleration
     
  4. Feb 2, 2006 #3
    What is the question? what is the problem with things you have done? Pls be specific.
     
  5. Feb 2, 2006 #4

    HallsofIvy

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    Science Advisor

    x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

    Yes, it is "the time being squared"- you didn't square! What is 52?
     
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