Questions tagged [moments]
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Calculating moment of inertia for a hollow discontinuous circle?
This is a pretty simple problem, but I'm just not sure how to go about it. I want to find the moment of inertia of a discontinuous hollow circle. But since the shape is so irregular, I'm not sure how ...
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Determine the moment of inertia of a filled circular sector
Does anyone know how to determine the moment of inertia of the filled circular sector shown below?
Apparently I have to use $dA=r\ d\theta\ dr$, $y= r\sin(\theta)$ and end up getting $I_x=\frac{r^4}{...
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is bending moment on roller supports at beams zero?
isn't the bending moment supposed to be zero on roller supports at beams?
then why isn't it zero here in this picture at x=2?
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Skewing of joints using virtual work
Given ist the following framework:
$$E=210 \frac{\text{kN}}{\text{mm}^2}$$
$$ EA \to \infty $$
$$ I_1 = 80000\text{cm}^4 $$
$$ \frac{I_1}{I_2} = \frac{3}{4} $$
$$ I_3=I_1 $$
Using the principle of ...
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What are the principles (if there are any) behind the conservation of bending moment in frame analysis?
I notice from this question that the moments at joint connection are somehow "conserved", or being "transferred" from one element to the others. In other words, there are no "missing moment".
Note ...
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Different measured strain in beam experiencing pure bending
I have a beam experiencing a pure bending moment. The setup is similar to this image from these lecture notes (with different values).
Using the flexure formula, we can determine that the stress (and ...
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A way to calculate the magnitude of the moment
In my engineering textbook, I didnt understand the example given to explain the magnitude of the moment. It asks to calculate the magnitude of the moment about the base point O of the 600-N force in ...
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Why is the bending moment equation for a uniformly distributed load (w) across a length x on a structure given by w(x)(x/2)?
So for any structure, simply supported beam, three hinge frame, cantilever etc. where there is a uniformly distributed load. For example, for a simply supported beam with uniform load of w along the ...
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Parallel beam load cells, force transfer and maximum load
I'm going to experiment with a parallel beam load cell like this one: https://cdn.sparkfun.com/datasheets/Sensors/ForceFlex/TAL220M4M5Update.pdf. I've read somewhere that for a setup shown on this ...
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Optimization: Most efficient way for multiple people to move boxes
We are moving house in a few weeks and have a couple of people helping moving the boxes. My previous experience from moving is of queues building up in small hallways and people getting tired from ...
user29236
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Is bending moment along a beam independent of the cross sectional area of the beam?
We know this that if the a cantilever beam (of any cross section) is fixed at one end and a transverse force is applied on the other, then it will bend. However, we just casually assume that the ...
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Flexural modulus for a beam fixed at one end
For a beam supported at both ends with a mass in the middle, the flexural modulus is given by:
$$E_b = \frac{F L^3}{48I d}$$
with I as the area moment
$$I = \frac{1}{12}wh^3$$
How does the ...
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polar moment of inertia for compound shape
I have a shape that I'd like to calculate the polar moment of inertia for:
the diameter is 600mm; the hexagon in the middle sides are 70mm each; the holes around the hexagon are 130mm from the center ...
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How do you calculate the shear force on the screws that connect a door to a jamb via hinges
I'm trying to calculate the shear forces on hinge screws or bolts. Here is a schematic of the door with the relevant values:
First, I took a free body diagram of the door and its hinges. The ...
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Transfer of moments in beams with internal hinges
We have a beam with 1 internal hinge just like the picture. We know the internal hinge can not transfer moments between AB and BD. We know the 30 kN force makes some moments on BD & AB. If B (...
user14854