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Particle acceleration and velocity Problem

  1. Jan 30, 2007 #1
    A particle is moving along a straight line such that its acceleration is defined as a=(4s^2)m/s^2, where s is in meters. If v=-100m/s when s=10m and t=0, determine the particles velocity as a function of position.

    Now I'm taking the integral of a but when I plug in the other parts, it doesn't work out. I think I'm doing something wrong.

    Someone please comment on how-to approach this problem step by step thanks!
  2. jcsd
  3. Jan 30, 2007 #2
    [tex]a(t)= \frac{d(s')}{dt} =4s^2[/tex]

    Move over dt integrate, set the limits, and solve.
  4. Jan 30, 2007 #3
    Can you explain a little further please?
  5. Jan 30, 2007 #4
    Which part?

    What dynamics book are you using? There should be a problem similar to this given somewhere as an example.
  6. Jan 30, 2007 #5
    after moving over dt to integrate, how did you approach it from there
  7. Jan 30, 2007 #6
    what do you mean? Show me some work please.
  8. Jan 30, 2007 #7
    how can i post the work here?
  9. Jan 30, 2007 #8
    Type out what you got and what you did.

    You can use [tex] and [ / tex] tags to make it look nicer.
  10. Jan 30, 2007 #9
    integral 4s^2 = (4s^3)/3


    4(10^3)/3 = 1333.33

    1333.33/10 = 133.33 = particle velocity at x position
  11. Jan 30, 2007 #10
    Are you familiar with the definition of acceleration?

    Which class is this HW for?
  12. Jan 30, 2007 #11
    It is for a dynamics class, I just want to get a head start on a set of problems that were given to me
  13. Jan 30, 2007 #12
    I think you need to review the basics of dynamics. What it means when they say acceleration, velocity, and position.

    I think you need to solidify the fundamentals before doing this HW. You should know better that acceleration is the second derivative of position by now.
  14. Jan 30, 2007 #13
    so you cant help me?
  15. Jan 30, 2007 #14
    Sure, tell me what the definition of acceleration is, and look for your mistake.

    I can point out mistakes, but im not going to teach you fundamentals. :wink:
  16. Jan 30, 2007 #15
    can you solve it and I can find my mistake, or post how.

    also acceleration is the rate at which a object increases/changes its velocity(speed)
  17. Jan 30, 2007 #16
    Ah, Im sorry. Its asking for velocity as a function of position. I was thinking you had to integrate twice.

    What you need to do: set up your limits of integration.
  18. Jan 30, 2007 #17
  19. Jan 30, 2007 #18
    Do you know what limits of integration are?
  20. Jan 30, 2007 #19
    yes integral from one value to another
  21. Jan 30, 2007 #20
    so what are your value you used?
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