Questions tagged [applied-mechanics]
Questions about using applied mechanics to model engineering problems.
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Doubt related to S-N curve
S-N curve is drawn from the results of fatigue test and fatigue test is conducted under completely reversed bending stress condition on a standard specimen. Is there any reason for conducting the test ...
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Why the iron bar holding the gondola lift is shaped in this way?
The Gondola lift has an upside down J shape iron bar holding it. I was wondering why it is built in this way and is not straight? Does it have anything to do with balancing?
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How to calculate the required power to pump out (to vacuum) a container?
Consider I have a cubic container with its volume is 1m cubic as in the simple picture above. It is sealed nicely, it is air proof, no air leaking. I would like to pump out (to vacuum) the container ...
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Fixed Free Fixed Free Rectangular Plate Subjected to a Point Load solved by FDM
The equation for deflection of a rectangular plate by using classical plate theory is given as,
Here Pz value on the RHS is uniformly distributed load acting on entire plate in Newton per metres.
...
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stress power of a solid
In the balance of mechanical energy https://pkel015.connect.amazon.auckland.ac.nz/SolidMechanicsBooks/Part_III/Chapter_3_Stress_Mass_Momentum/Stress_Balance_Principles_08_Cons_of_Mech_Energy.pdf,
$\...
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Saturation of penetration length using Lucas-Washburn equation
The Washburn equation for capillary flow provides the following expression for the calculation of the penetration depth (or capillary rise):
$L \propto \sqrt(t)$
My question is when t goes to infinity,...
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What would be an ideal material to use for O-rings on a canister in a lubricant-less, high-velocity pneumatic tube system?
I am interested in building an experimental lubricant-less pneumatic tube system in which the canister will be propelled up to a high-velocity, reaching a peak velocity of approximately 100 m/s before ...
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Input power unit for Heavy Duty spool hose
I'm trying to design a machine for spooling a hose at a mining application.
Considering all hose length, mass, spooling diameter and pump the peak torque would be of To = 10267 Nm.
It sounds a lot but ...
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Can I use this simple pulley system to lift a large 100lb box?
Problem: I have a 98 lb box with dimensions of 45"l x 41"w x 27"h that holds a holiday decoration. I need to lift it to a shelf I made that is 103" above the floor. The space I ...
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How to find Tensile Modulus of a layer of Plain Woven GFRP with GSM of Fabric given
I need to Input "E" the tensile modulus for analysis of a composite layer made from Plain Woven E-Glass Epoxy composite material.
I know the GSM (g/m^2) of fabric is 106.
Using GSM =106, ...
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What causes an EUC to propel forwards when leaned forwards?
If this question belongs to physics stack exchange, please let me know and I will transfer it as soon as I can. Please also let me know if a diagram is neccessary of the model (I have not made digital ...
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Applications of overdamping, critical damping and underdamping
I am a math lecturer and in my teaching of second-order linear differential equations I present, as an application, the classical mass-spring-dashpot system (and its RLC analogue). According to my ...
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How to change the direction of a chain-sprocket system
I’m looking for a way to change the direction (90 °) of a motion transmitted by a basic chain-sprocket system. Is there such a thing as a chain-driven equivalent to straight bevel gears?
I’m planning ...
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Sequential installation of pumps from the point of view of mechanics
Let's say we have a case of sequential installation of identical pumps in a pipe with a diameter equal to its entire length, water flows in this pipe. Since when the water passes through the first ...
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What is wrong with the derivation for x coordinate of Centroid of quarter of a circle below?
In the derivation for x coordinate of centroid of a quarter circle as shown in the image below why is the sign coming out to be negative when actually it should be positive?
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Finding hoop stress in a half-cylinder
I have a half cylinder which is significantly thick but not very long. In the half cylinder, a force $F_{app}$ is being applied over a certain area as shown in the figure below:
I have to find the ...
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What kind of sensor can I use for measuring the rotational position and speed of a link in a fourbar mechanism?
I work in mechanism circuit breaker design. We typically use mechanism that utilize small Θ and we therefore measure using linear travel potentiometers. On this new design, I need to measure a larger ...
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Approaching/formulating a problem in solid mechanics
Consider a thin surface and hold it tightly and vertically at a point on its boundary. What it is the shape it assumes?
As a particular example let's take a circular plate clamped on a plane, as shown ...
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Is splitting torque a possible solution for a passive CVT?
Would it be feasible to design a passive CVT gearbox that converted input rpm into an output of always N by splitting the input (such as is split in a helicopter transmission) then inverting the ...
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Lifting Analysis of a 3D cuboid
I have a cuboid of weight W and the Center of Gravity at G. It is being lifted using 4 inextensible strings from the 4 corners: $C_1$, $C_2$, $C_3$ and $C_4$. The figure is something like this:
The ...
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how to fix an object at either 90degree or 0 degree
my problem is i donot know how to let the blue colored object be fixed at either 0 or 90 degree.
i dnot want to be moveable at any degree like 30, 40 , or 50 degree either 0 or 90 degree.
i have tried ...
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How to limit rpm to 100 on bi-directional input shaft no matter the torque up to 10hp. Right angel gear box. 1:6 increaser rpm output 600rpm
How to limit rpm to 100rpm on bi-directional input shaft no matter the torque, up to 10hp. Right angel gear box. 1:6 increaser rpm output 600rpm
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How to use low pass filter in lock-in amplifier?
I am doing the pump-probe experiment.After the reflection of probe beam from the sample it is passed through photodiode and then to lock-in amplifier. Now I need to extract unnecessary noise from ...
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How to find the displacement of an arbitrary point on a spring?
Consider a spring fixed from end A and pulled from the other end B. The displacement of the end B of the spring is $x$.
If I take a point at a distance $l_1$ from end A, how can I determine the ...
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How to Calculate Damping Ratio and Natural Frequency of a Mass Spring Damper system, excluding air resistance?
In summary, I need the damping ratio and damped frequency of a system excluding air resistance, as the system will be operating in a vacuum. The system can be modeled as a mass-spring-damper, and the ...
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Could a downwind cart, or “push-me, pull-me” boat of a substantially heavier size be propelled with the use of a CVT, or continuous gear?
As broadly proven now before the academia, a vehicle including a boat or cart (probably a glider too) can move faster than the speed of wind up to about 2.5-2.8 times with a propeller generating lift ...
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Does the surface finish of the strings on a musical instrument impact the timbre?
Suppose we are testing out different unwound strings on a piano.
Each of the tested strings is made of the same material, has the same length, same diameter, density, etc., the only difference being ...
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Problem of lifting of a body using 4 strings
I have a solid object that has been lifted to a hieght by 4 strings. I know the lifting point and the 4 corners of the object. Also the mass and the center of the gravity location of the object is ...
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Does the inertia of a beam section include the material density?
Sorry but I'm a little rusty. When solving a beam of any type of section, must the density be included in the moment of inertia of the section?
For example, if I see Navier's formula, I would say ...
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how much pounds of pressure does a screw on perfume bottle cap vs a mechanically applied perfume bottle spray mechanism for a bottle exert?
What would be the difference in pressure between a screwed on bottle cap like the ones you see on a refillable perfume bottle screw on top such as this
https://www.ebay.co.uk/itm/154178728592?hash=...
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Are there any advantages of using BEM for contact problem over FEM, apart from lesser computational cost?
FEM - Finite Element Method
BEM - Boundary Element Method
If we had access to "enough" computational resources (to discretize the entire volume domain in FEM to the same degree of fineness, ...
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How to calculate the degrees of freedom, constraints and the generalized coordinates in this dynamic system
The rope lengths are taken to be constant.
Solution:
$N$ particles with $k$ constraints.
. Then the Degree of Freedom (DOF) is $3N-k$.
In Figure 1, we have two particles $m_1$ and $m_2$, so $N=2$. But ...
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Incremental encoder with memory
I'm working on a robotics project. In this project we need to control the angle position of the wheels. We are going to use an incremental encoder (we didn't find an absolute encoder that was able to ...
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Calculation on gearbox design
I want to design a gearbox of 70hp input motor and speed of 1400rpm. The gearbox ratio is 1:10 of 2 stage parallel arrangements.
How do I calculate for the teeth, modules and other requirements ...
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what is the minimum number of reinforcement bars in a circular tie rod?
I know that the minimum number of reinforcement bars in circular concrete section of columns are 6, is it the same for circular tie rod section?
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Velocity of blocks under different situations
Height of all blocks is 100m.
CASE 1:
Blocks are at a distance of 100m in height. When they reach the ground , velocity of 1st block must be higher than velocity of second block due to the extra ...
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Calculating torque in planetary gearbox
It's my understanding that in a planetary gearbox, force moves through the system via four mechanisms: the ring gear, the planet gears, the planetary carrier, and the sun gear. I'm trying to ...
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Work done by a force in a deformable body
Consider a deformable body that is acted upon by several forces at different points of application.
Under these forces, the body remains at rest but deforms and the particles have some displacement. ...
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Is kinetic energy on a body in vacuum = 0?
We know kinetic energy =$\frac{1* mv^2}{2}$- $\frac{1* mu^2 }{2}.
$.
u=initial velocity & v=final velocity.
So , for a body in uniform translational motion I.e acc=0 & velocity is constant. ...
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How to solve this complicated truss system?
Below is a truss I simulated in a truss calculator. I'm just wondering, how to solve for the compression and tension of each member and are there any method that can solve this?
My solution is I ...
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Center of gravity
Say an aircraft without its engines has a mass of 118 tonnes and balances on its rear wheels only. This must mean the center of mass of the aircraft without its engines is directly above the rear ...
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What should be the mass of block A so that the system stays at rest?
Q: What should be the mass of block A so that the system stays at rest ?
Conditions:
i) No normal force is present at point of 2kg mass. It doesn’t mean N=0.
ii) No friction , mass of string & ...
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How to Calculate Approximate Fuel Consumption from Engine Specs
I have a marine diesel engine, and I'd like to calculate the approximate fuel consumption based on the size of the engine, at a given number of RPM - specifically for the cruising recommended cruising ...
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How to replace these two forces with one force?
Here, $P>Q$. $O$ is the center of mass of the rigid and uniform bar/stick.
As $P>Q$, the resultant is situated to the right of $\vec{P}$ and is parallel to $\vec{P}$. The magnitude of the ...
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I have a question regarding moments and centre of mass
Lets say a plane had 2 engines located 9m ahead of its rear wheels. Give each engine a mass of 7.5 tonnes. A force of 147150N will act 9m ahead of the rear wheels. lets say the aircraft was 133 tonnes ...
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Does the constraint equations written for pulley mass system can be any coordinate system other than rectangular
This is an example problem from the book vector mechanics for engineers. I had a doubt that how the position vectors for A and position vector B relative to A defined. That is the equation which is ...
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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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Modelling a Simple Translational System
I posted this on stack exchange physics, sadly no one has answered so I thought I'd try my luck here.
I am trying to model the following translational mechanical system in I/O form, however I am ...
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Stress-strain Curve Interpretation
A significant barrier to my understanding of typical engineering stress vs. engineering strain curves is that for certain values of stress, there are multiple values of strain (i.e., the stress-strain ...
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Eight bar Linkage (Analytical solution)
Good morning,
I'm trying to solve this problem of kinematics of an eight bar linkage through the analytical method.
I don't want that you perform the calculation, only I would like to have a advice ...
