Questions tagged [moments]
The moments tag has no usage guidance.
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What causes an EUC to propel forwards when leaned forwards?
I have heavily edited the question, as its previous standing was quite hopeless
Thinking about a simple model of a unicycle, where the rider is a uniformly distributed rod and the unicycle just ...
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Is the maximum bending moment of a fixed end beam always at end?
Mathematically, we can see that with downward loads only (only upward loads at the ends), the maximum bending moment for a fixed end beam of span $L$ either occurs at $x=0$, $x=L$, or where the shear ...
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How does a single point load cell eliminate the inluence of moment/load placement
All descriptions I have been able to find mention some variation of "due to their geometrical design single point load cells are immune to load placement" with no explanation on how is it ...
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Calculate compressive stress in shaft/key surface from torque
When designing shaft keys we calculate compressive stress in hub/shaft/key and compare it with allowable stress. The usual formula is
$$p = \cfrac{F}{A} = \cfrac{\cfrac{M}{R}}{L_e \cdot t}$$
where $p$ ...
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Why is there a negative sign in case of moments caused by longitudinal stresses?
I came across the following relations in the plate theory. I, however, don’t understand the reason for the negative signs in Mx and My. There is, however, no negative sign in Mxy. I am guessing, this ...
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Horizontal "pinching" force of an arch with applied moment
I have some Shape Memory Alloy wire programmed to curl from a straight beam into a circle. The force this generates is approximated as a uniform distributed bending moment along the length of the wire....
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Max bending moment estimate
Context: I study aerodynamics and want to design and build an RC wing to put the theory I learned into practice. The essence of the theory I learned is: Given some mass of wing building material, how ...
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Torque calculation for DIY friction wheel drive electric unicycle
I’m building a friction wheel drive electric Unicycle.
Something like this;
My question is how much torque should the friction wheel drive motor have considering the total mass of unicycle including ...
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Are you able to compute the bending moment exerted on the inner edges of parallelepiped box under inner pressure?
Suppose you have a parallelepiped box of dimensions $a\times b\times L$ with $L\gg (a+b)$, filled with simple distilled water exerting a uniform and constant inner pressure $p$ as reported in figure.
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What is the difference between mass moment of inertia and area moment of inertia? And why mass moment of inertia alone used for kinetic rotation?
What is the difference between mass moment of inertia and area moment of inertia and why mass moment of inertia alone used for kinetic rotation? Is there a possibility to use them interchangeably?
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Moment of a force
How come when I try using the formula M = rF (sintheta) I get Moment at D = .223 * 300 * sin(25)= 28.4 Nm but it's wrong.
The answer uses cross product but I thought I could just use the magnitudes ...
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Is there a way to solve this complex statics problem algebraically?
This problem can be solve in 2 ways either I solve it with vectors which would be relatively painful and more time consuming and the other faster way is algebraically but I faced a problem when trying ...
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Torque for servos of tiltrotors
I am sourcing a servo for a tiltrotor drone and need to calculate the required torque to rotate the propeller and the motor from facing the front to facing the top. I understand that the minimum ...
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How to calculate the moment of inertia of a propeller
I am trying to design a VTOL system that uses a servo to rotate a propeller and the attached motor so that it can provide thrust when it is at 0 degree and lift when it is at 90 degree. However, I ...
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Understand how to choose the pivot point to calculate the moment of forces in dynamics
In statics, the net force and the net torque must be both zero. The net torque is the vector sum of all the involved torques (first moment of each force) about any arbitrary point $P$. The point $P$ ...
