Recent content by studentoftheg

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    Length & Bending Stress: How Does Beam Length Impact Stresses?

    Right, I see now. So the resultant moment at the anchor will increase as you increase the length of the beam. I was picturing it wrong... Thanks again
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    Length & Bending Stress: How Does Beam Length Impact Stresses?

    Thanks Matt, OK well maybe I'm not picturing this correctly in my head. I know that a moment = force x distance (from point of interest), but in my example there is an applied moment to the end of the beam (irrespective of the length of the beam). As I stated above, the bending stress is M*y /...
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    Length & Bending Stress: How Does Beam Length Impact Stresses?

    if you have a beam or something, anchored at one end and apply a moment at the other end, then the bending stress is given by M*y / I, where I is the moment of inertia of the beam. what affect does the length of the beam (i.e. the distance between the anchor and the end of the beam, where the...
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    Trouble Understanding Bending Moments?

    Thanks, no that wasnt clear to me, that's what I'm having trouble processing and picturing in my head. So if it bends in XY axis then that is a moment about Z? And so I take it applying a moment about one axis then results in bending in the other two axis'? So if I applied a moment about Y, then...
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    Trouble Understanding Bending Moments?

    Thanks for replying. I know this is pretty basic stuff! Yeah in particular its the resulting direction of the bending moments within a beam. For example, which direction would you need to apply a force to get a moment about Z etc?
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    Trouble Understanding Bending Moments?

    Anyone point me in the right direction here? Thanks
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    Trouble Understanding Bending Moments?

    Yeah I am talking about the bending moment within the beam as opposed to reactions at supports etc.
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    Trouble Understanding Bending Moments?

    I'm having trouble fully understanding bending moments. I get the calculations, the force times distance (lever arm), and how to calculate the bending stress (M*y/I). Its the orientation/direction that I am having trouble picturing in my head. I know this is pretty basic, but I just haven't...
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    Calculating the natural frequency of a piping system

    yeah I've been doing some reading over night, i think it might be due to the effective force being overly conservative. there will be 'feed in' to it, which will reduce the compressive force. thanks
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    Calculating the natural frequency of a piping system

    I'm calculating the natural frequency of a piping system that is spanning between two points, the formula is the square route of various terms, including the effective axial force in the piping. This is taken from a design code, see below: f = C * SQRT[(E.I/M.L^4)(1+Seff/Pcr+C.(d/D)^2] C =...
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    Terminal velocity of an object falling through a liquid

    Ok so to clarify... I only changed Mtotal (the total mass), the submerged weight stayed the same as I didnt actually change the mass, I just increased Mtotal (from submerged weight+added mass, to mass in air+added mass). And to calculate the terminal velocity you set dv/dt=0 so Mtotal is...
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    Terminal velocity of an object falling through a liquid

    The drag force equation is: 0.5 p * (Cd* A) where p = density of liquid Cd = drag coefficient for object A = drag area So this doesn't change. Only thing I change is Mtotal.
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    Terminal velocity of an object falling through a liquid

    Yeah the equation of motion is: Mtotal dv/dt + Fdrag v(t)^2 - Wtotal = 0 Where M is the total mass, Fdrag is the drag force (proportional to the square of the velocity) and Wtotal is the submerged weight. The surface area of the object did not increase at all, I only increased Mtotal...
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    Terminal velocity of an object falling through a liquid

    I have a question regarding the terminal velocity of an object falling through a liquid. Now the speed will increase up to the terminal veloity in a given time. What I do not understand is in this calculation I'm performing (solving the equation of motion for the speed, when acceleration equals...
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    Linear Electric Motors: Pros & Cons

    Thanks, so what would one of these be? http://www.copleycontrols.com/Motion/Products/Motors/stb.html Also, for matching up requirements, say you had an electric motor with a torque of 10Nm. Could you divide this by the length of the lead screw (or whatever type of shaft your using to...
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