2
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Dynamic forces in Simulink
The sign function gives zero friction force for zero velocity, which is generally not correct (and leads to the artificial oscillations, as the integrator is made for smooth systems and cannot handle ...
- 96
2
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Accepted
Why Do the Fingers in Mechanical Pencils Fly Out?
The plastic fingers are moulded in the open position. During assembly and operation they are compressed.
I imagine that the fingers are moulded so that with the ring in the position shown they are in ...
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How to calculate wind impact to DIY solar panel array frame?
From your units, I'm assuming you're based in the US ?
Have a look at the skyciv online wind calculator : https://skyciv.com/wind-load-calculator/
It has support for sussing out wind loads to ASCE7-16....
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How to calculate force acting on axle from hub motor with known torque?
Assuming the motor has a Torque of 40Nm, what is the force on the fork centred at the axle?
Since the system is fixed in place, there is no acceleration or rotation. Therefore any torque developed ...
- 136
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A question on understanding the nature of static equilibrium
In Engineering, we are usually not concerned with the detailed molecular level of material behavior. That is the job of material scientists and engineers. We assume a point load on a slab or on top ...
- 22.8k
2
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Understanding the nature of Force and Moment FBD diagram
Premise
When you analyze the equilibrium of a body you first have to be sure that it is in a static configuration. In other words, it's bound to enough external constraints such that the reaction ...
- 104
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can I use SS316 bush in Aluminum bronze body?
Aluminum alloys and stainless steel are both corrosion-resistant because of the stable oxide layer that naturally skins them over and protects the base metal from further oxidation.
This layer is thin ...
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1
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Could moment be an imaginary concept?
Torques are no more or less imaginary than forces. There are several conservation laws in our mathematical description of the world. One is linear momentum, which is governed by a force law; and ...
- 5,105
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Help understanding why bending moment is integral of shear
Short answer to address your confusion is that moment $M(x)$ and transverse force $V(x)$ are basically independent quantities if you are looking just at a specific coordinate $x$ (e.g. there will be ...
- 1,460
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Help understanding why bending moment is integral of shear
Let $\Delta V = w_x*\Delta x$, and $\sum M_B = 0$
$- V_x*\Delta x -\Delta V*\frac{\Delta_x}{2} - M_x + M_{x + \Delta x} = 0$
$- V_x*\frac{\Delta_x}{2} - V_x*\frac{\Delta_x}{2} - \Delta V*\frac{\...
- 8,232
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vote
Accepted
How do I relate tongue weight to weight x distance?
you need to jack up the car and check the structural layout of the hitch. Usually, there are two arms welded to the sides of the hitch receptor reaching to the left and right side of the mainframe of ...
- 22.8k
1
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Why does restoring force of a spring vary directly with elongation or compression?
Metals don't stretch by moving apart: they stretch by moving sideways. Atoms move tangentially to their bonds. Strain at the lattice level is not aligned with strain at the macro level. Look at a ...
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Why does restoring force of a spring vary directly with elongation or compression?
Hooke's law is an approximation good for small values of spring deflection. Here is why it's a good approximation:
In a chunk of material being pulled in a tensile test, the pull force is very tiny ...
- 15.3k
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Calculating forces of TV wall mount with long extended arm. Need help with Physics, torque vs force and anchor requirements
The important thing here is taking into account the dynamic load on the mount. Such as the impact of the vibration of banging a door or swinging the TV bracket into a new position. A dynamic load ...
- 22.8k
1
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Hertz contact pressure formula for cone on a plane
Your case is a special case of Hertz contact forces between two cylinders. Except one has a radius of infinity. Say in the figure $D_2= \infty$. source.
'
The equations are:
$$ { b = \sqrt{\frac{2F}...
- 22.8k
1
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A question on understanding the nature of static equilibrium
What you describe in your first example is perfectly covered by usual engineering calculations and is described by the Poisson effect. When you squish a solid (in this case, by its own weight) said ...
- 306
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How to calculate stiffness to weight ratio of one big tube vs two small tubes (see drawing)?
Caveat: I asked the question and give an answer here myself that takes the specific numbers given in my question and applies them to the formulas in the answer given by Tomas Letal. I do not have the ...
- 23
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How to calculate stiffness to weight ratio of one big tube vs two small tubes (see drawing)?
Lateral stiffness
Assuming the plates stay parallel, you can use lateral deflection of beam end while keeping the 0 rotation there. Replacing one of the plates with a force-moment couple, $F_1$ and $...
- 1,460
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vote
Accepted
How to calculate the mechanical advantage of torque reaction arms (or balanced articulated arms)?
In each joint, The moments are the weight of the load plus the weight of the lift arm(s) multiplied by the distance to the joint.
setting the moments sum about the joint equal to zero will give ...
- 22.8k
1
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How to calculate the volume of a partially submerged horizontal cylinder and the center of buoyancy?
Assuming balanced loading, meaning the results of the load placed on the buoy and its weight are passing through the CG of the buoy the 4 cylinders are submerged equally to a depth of H such that the ...
- 22.8k
1
vote
Pull out force for a 5/8" tapped bolt
Short Answer:
12,000 lb and not necessarily
Long Answer:
For a rough estimation, let's say you are using a grade 5 bolt and A500 grB tubing, and let's assume your thread engagement length is 1/4"....
- 31
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Accepted
How to calculate forces on bearings in a chain drive
Assuming the shaft and sprocket masses are small and performing static analysis:
If you have an output torque $T_\text{out}$ on the output shaft, and the sprocket diameter is $d$ then chain force $F_\...
- 423
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vote
Accepted
Finding hoop stress in a half-cylinder
The sketch above forms the base for solving reactions at "a" and "b". Note that if the loads are acting on the near edge, then there is a twisting need to be considered.
Without ...
- 8,232
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Accepted
Angle of attack for torque calculation from buoyancy force
you should use angle 2. The buoyancy in this case is due to pressure from 3 sides. the 2 lateral sides undergo triangular pressure distribution that opposes each other and cancels.
Therefore the only ...
- 22.8k
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Dynamic forces in Simulink
This is how it (time stepping, an alternative to event-detection algorithms) can be done in Python (I am afraid having neither SimuLink nor MatLab at hand, but the algorithm should become clear)
...
- 96
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I am designing a light that is hung from the end of an arm. How do I calculate the amount of force on the fastener where the arm attaches to the wall
Say the arm is 2 inches vertically at the base where it is hung by the fastener and the distance between the fastener and the point of pressure is 1.5 inches.
$$F_{fastener}=\frac{8lbs*27in}{1.5in}=...
- 22.8k
1
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Accepted
I am designing a light that is hung from the end of an arm. How do I calculate the amount of force on the fastener where the arm attaches to the wall
Convert mass and radius to Torque. The force would be distributed between fastener wall contact areas unevenly with very high pressure on the bottom edge puncturing the wall with the same torque but ...
1
vote
Accepted
Calculate uphill efficiency on different gears
You found that the total energy needed to climb the hill is the same despite using two different gear ratios. This is in fact correct because of conservation of energy.
Look at is from another point ...
- 81
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Force required for a power generator in a coal power station
It is common practice to "motor" a turbine/generator assembly slowly in the absence of steam or water flow, while maintaining full lubricating oil pressure, so the sheer weight of the blade ...
- 15.3k
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