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    Engineering Stress and deflection of wheel drum ribs

    This is exactly the sort of problem FEA was created to solve. I think you will be wasting your time seek a simple formula for stress and deflection in the ribs. If you want something to check, I suggest that you modify your FEA model to something that can be readily analyzed by classical means...
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    Does studying Latin help in learning other languages?

    The two most useful courses I took in high school were geometry and Latin. I did great in geometry and poorly in Latin. Despite my poor performance in Latin, it has proved extremely valuable in the 60+ years since I left high school. I would strongly recommend it to anyone who wants to be educated.
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    A Bar hanging from two springs with unequal masses

    The correction is actually incorrect. The bar itself is massless, so you do need to use the parallel axis theorem to get the MMOI for the system about the system CM.
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    How is the turbine speed controlled by Grid but not by itself?

    Sounds about like a place I used to work some 44 years ago.
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    Automotive Can I have a multi-stage reciprocating compressor?

    To see the process in reverse, look on the net for a triple expansion steam engine. For such a machine, the same steam is expanded through three stageds.
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    A Bar hanging from two springs with unequal masses

    As is so often the case, you have leaped into the dynamics without paying adequate attention to the kinematics. Until you figure out how to express the positions of the masses in terms of your generalized coordinates, you will not make any progress. Ask yourself first, what are x, y, and theta...
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    How to study Mechanics, and what after it?

    I would strongly suggest getting a basic engineering text on Statics & Dynamics (by authors such as Beer & Johnson, Bedford & Fowler, Meriam & Kraige, etc, etc.) There are dozens available, and you should be able to get a used copy really cheap on the 'net. This has the advantage of providing...
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    How is the turbine speed controlled by Grid but not by itself?

    Even with engine-driven gen sets, where several set supply a small system, they are effectively locked together by electromagnetic torques. An additional set cannot be brought on line until the speeds are matched and also the phase angles. A point that does not seem to have been brought out is...
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    What is the force required to upright a tipped drum?

    We need dimensions for thee drum and need to know if it is full. If not full, what portion is filled?
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    For WW1 & WW2 History Buffs

    It is impossible to make any sense at all of WW II without a hard look at WW i and even the period before that time. It all ties together.
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    How to estimate a constant drag coefficient of a boat?

    Effective hydrodynamic drag is strongly dependent on wave making which in turn depends upon hull length. Wave drag is a separate issue from viscous drag.
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    Torsional moment vs bending moment

    In structural analysis, the terms "bending" and "torsional" usually refer to transverse and axial moments respectively. These are essentially local definitions.
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    Python Automatic vs Symbolic differentiation

    Evidently I am arriving late to the party. What is the algorithm that you use for what you call "automatic" differentiation? (I know nothing about Python, so please describe the algorithm in mathematical terms; thanks).
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    How do I correctly move into engineering?

    Yes, what is needed for a particular job always depends upon the nature of the job. But to carry russ watters' argument a step further, that same person doing CFD on an airfoil will likely need to know something about flutter (fluid-structure interaction), and for that, the mechanics of...
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    I Measuring Tensile Strength in an alternative way

    When you roll the material into a cylinder, you prestress the wall, so that is one place this test differs from the conventional tensile test. Secondly, there is the matter of sealing the ends of your cylinder. Any feasible sealing technique is going to change the boundary conditions, again...
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    Other Is it a bad signal that it is taking two weeks "awaiting decision" for my journal submission?

    Anything less than 6 months sounds normal in my experience.
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    Admissions Can I apply to grad school in my 2nd year of undergrad?

    This does not sound like a great educational plan to me. If I were still teaching (which I'm not), I'd look at it with a jaundiced eye. I would suggest take a little long as an undergraduate, explore some additional upper level courses both in and out of physics, and give yourself time to mature...
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    How do I correctly move into engineering?

    The only way you will be fully competitive with an ME or AeroE graduate is to take the whole undergraduate curriculum. That said, however, if you can narrow your career objectives a bit, you can take only the undergraduate courses that support that area. As an example from long ago, when I was...
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    Member jim hardy has died

    This reminds me a lot of the house where Jim and Anne lived! Same "arrangement."
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    Member jim hardy has died

    Here is that last e-mail from Jim, along with the photo. I left Denver Monday, am at my sister's house in Tulsa. Plan to leave Saturday for home... We watched "The Music Man", one of Anne and my favorite movies. I bought the DVD . It still brings me to tears , dont quite...
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    Member jim hardy has died

    For several years, Jim put huge effort into caring for his wife, Fair Anne (the Lady in the Sun, as he called her) as she went through a long, slow decline with cancer. My wife and I visited Jim and Anne at Christmass time, 2017, and she was struggling then; she lasted until just a few weeks...
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    Modeling a Pendulum

    For very small displacements, the rubber band will act approximately like a spring. For larger displacements, you will find that the rubber band is nonlinear. From you description of the system, it sounds like the rubber band will only be taut for displacements to the left. You will need to take...
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    Wood/Glass/Metal Wooden hydraulic mechanical arm

    Whoever built this did a very nice job. It is a fine demo rig.
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    Physics Jobs during a PhD

    I've known lots of students who held TA positions and similar while working on a PhD. I would say that any on-campus job is OK during the early part of the PhD program, but towards the end, the studies are too intense to allow for additional work.
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    Job Skills Value of an engineering PhD versus a Masters ->Industry

    I think marcusl may well be correct as far as starting salary and position title is concerned. I do not think this is correct with respect to the career path that it leads to. For most engineers that I have known (which is a lot!), they start off working under someone designate the "project...
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    Job Skills Value of an engineering PhD versus a Masters ->Industry

    I certainly do not think this equivalence applies in any part of engineering that I know about. I think there might be some equivalence between a BS and 3 years experience versus an MS, but a PhD is always expected to go well beyond that point in my own experience.
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    Pendulum Hammer Impact Force Calculation

    I thought we put this one to bed over at the ME Forum. Is there something new required?
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    Job Skills Value of an engineering PhD versus a Masters ->Industry

    I agree all the way with PhantomJay. Only for a few narrow employment scenarios is a engineering PhD required.
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    Chernobyl Alternative to generators to prevent the Chernobyl disaster

    Yes, there may be additional delays. I am still surprised at the 60 sec figure.
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    Chernobyl Alternative to generators to prevent the Chernobyl disaster

    My experience was specifically with standby gensets for the American nuclear industry, although I cannot identify the specific plants.
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