Recent content by LFS

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    Question regarding Pipe flow

    This is a chicken/egg question: parabolic or navier-stokes? I "read/know" that the velocity profile for laminar flow is parabolic with v=vmax as maximum and v=0 on the edges let us say D=2d. Mathematically I immediately say: the equation of such a parabola is v=vmax•(1-x²/d²) for xε[-d,d]...
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    Proof of Pascal's Law

    Homework Statement My son was given a proof of Pascal's Law and told to learn it for his course in Fluid Mechanics. a. It was done with a prism. I cannot type in a link, but google: pascal law prism and pick the first link and scroll down half a page to pressure and you will see this proof. b...
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    Area moment of inertia of inverted triangle?

    Hiya TinyTim, I am sure you are absolutely correct that the area moment of inertia Ic depends only on shape. However, "area moment of inertia" is just 4 words to me (no physical meaning). Meanwhile, I did find the integral formula for computing the center of pressure (Fox) and calculated it...
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    Area moment of inertia of inverted triangle?

    Hiya Tiny Thank-you for your response. Those were exactly the links I was going to put in (but wasn't allowed). The reason I ask is that the centroid of a triangle is 1/3 of the height measured FROM the base (i.e. from the weighted position of the triangle). So the (depth of the) centroid...
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    Area moment of inertia of inverted triangle?

    Homework Statement A inverted isosceles triangle gate with height a=3ft and base b=2ft is 6ft under the water (top of the inverted triangle). Find the Force on the gate and hp (the depth of the) center of pressure. Homework Equations hc= depth to gate + depth to centroid= 6+(1/3)•3= 6+1 =...
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    Standing waves, aluminium, speed of sound

    1. I am a mathematician trying to understand a physics experiment where an aluminum rod is held in the middle and struck with a mallet. The rod is then placed next to a microphone, the sound recorded and the frequency determined using Audacity. Working backwards, one determines the speed of...
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    Need help with a calculus problem?

    Thanks and links fixed Thanks dontdisturbmycircles for the kind words about the mathcasts and thanks minase for noticing the dead links - which hopefully are now fixed! LFS