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Simple harmonic motion

  1. Oct 12, 2006 #1
    hey guys, just hpoping sum1 could point me in the rite direction....i cant wrk out how to proove v^2=n^2 (A^2-x^2) from

    v dv/dx = -n^2x

    obviously you hav to integrate...but i dont know how they get the A into the equation??

    what i hav tried is intergating both sides with recpect to x first

    v dv/dx x = (-n^2x^2)/2 and given we know dv/dx . dx/ dt = -n^2x and v = dx/dt the sub in to have

    .....well it brings me no where actually hence this post

    thanks for you help
  2. jcsd
  3. Oct 12, 2006 #2


    User Avatar

    Integrate both sides wrt x, giving you:

    integral v dv = -n^2 integral x dx. This, with intial conditions( v=0 at x = a), gives you the required quadratic.

    Next up,

    learn to spell and write English.
  4. Oct 12, 2006 #3
    well thanks for that, and im sorry about the english....just typing quickly and didn't realise correct grammer is required in a Maths forum....but never the less thanks
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