Recent content by comicnabster

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    Lateral Stress - need clarification

    Homework Statement (copied from a materials science assignment) During imaging the AFM tip may experience large frictional or adhesive forces or may come into contact with steep edges on the sample surface. Under these conditions AFM cantilevers are subjected to relatively large lateral...
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    Crystallographic planes and square pyramids

    Homework Statement In materials science right now we are learning about miller indices and crystallographic directions, including planes. What is the aspect ratio (height/width) of an AFM (atomic force microscope) silicon tip in the shape of a square pyramid where each face of the pyramid...
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    Derive the Period of an Oscillating Sphere

    You were trying to use trigonometry and torques, which overcomplicated matters and thus got you confused. It's ok, I've had my fair share of experiences where I try to apply unneeded concepts to a problem and make things harder for myself :(
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    Derive the Period of an Oscillating Sphere

    I just used what was shown here: http://www.egglescliffe.org.uk/physics/gravitation/balls/aproxg2.html Enjoy :)
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    Derive the Period of an Oscillating Sphere

    Hey, I have to derive the exact same equation for my lab too O_O
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    Stress in a concrete support column

    I described it as a cone with the top end cut off
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    Stress in a concrete support column

    All right, I think I got it this time! So the stress is actually uniform throughout the column, thus it must also be 12 MPa at the top. I used integration to get the volume of the column (revolve around x-axis). Conclusion: Lower radius = 0.527 m, upper = 0.510 m
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    Stress in a concrete support column

    Thanks, but now I have another question - how do I find the volume of a trapezoidal cylinder prism? I know how to find the volume of a trapezoidal straight-edge prism but not for the type where the bases are two circles of different areas.
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    Stress in a concrete support column

    Homework Statement As quoted from the question sheet: When building a tall support, often the self weight of the support must be considered. For an optimal support, the volume of material, and hence the cost, will be a minimum. If the maximum allowable stress in concrete is 12 MPa, determine...
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    Structures and Materials problem - stress and strain

    Homework Statement A 4000 kg car traveling at 160 km/h crashes into a concrete post. If all the kinetic energy of the car is used to crush the low alloy steel at the front of the car, how many kg of steel will be crushed before the car stops? Properties of low alloy steel from a table of...
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