Questions tagged [statics]
Statics is branch of engineering concerned with the analysis of forces and moments on physical systems in static equilibrium.
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Calculating deflections on an inclined beam
I'm applying a force to a stepped inclined beam (that's what I'm calling it; don't know what the correct technical term would be) in which it's essentially a cantilever with the first section angled ...
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Torque created at bottom left corner due to torque in centre of 2D box
If I have a 2D box with uniform mass of width $w$ and height $h$. I apply a torque $\tau_O$ to the centre of the box, labeled $O$. The box has a fixed point $A$ at the bottom left around which it may ...
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Mass and Tension in a Pulley System
I found the value for M2, unsure how to proceed from here. I got a wrong answer for T.
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Determining bearing pressure between mating convex and concave conical surfaces?
(In the illustration above, the "Collet" piece in the middle is a bushing)
I'm designing an axial linkage of sorts, and I'm having trouble finding resources, theorems, or guidelines for ...
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How to determine the flexibility coefficent of this six member truss using the unit-load method?
I'm studying the Flexibility method described in the book "Matrix analysis of framed structures" by James M. Gere but I'm having a hard time understanding one of the examples. I'm stuck at ...
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Minimum torque required to turn a large gear
I want to preface this by saying that this isn't homework, it's just a question I've made up myself (so it could just be impossible to solve), and I am a beginner so apologies if I miss something ...
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Finding the bending moment diagram for an indeterminate continuous beam
In a recent lecture, we had the following example of an indeterminate continuous beam where we must find the redundant support reaction at $A$:
This was found by removing the support at $A$, and then ...
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Statics HW Problem: determining magnitude and direction of resultant
The above shows the question and my work. I am confused on why my original solution does not get me the correct answer
If I sum x + y + 35 = 40 + 75 + 35 = 150, I am not getting 180 degrees which ...
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Available alternatives for ForceEffect? (Quick and simple static analysis)
Any recommendations for apps that have similar functionality to Force Effect (which was discontinued a few years ago)? The ability to do a super-quick static force analysis would be handy. (see https:/...
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Reduction of system of vectors
This is problem P2.6 from the Fundamentals of Applied Dynamics of R. A. Tenenbaum.
P2.6 Consider the system made up of the sliding vectors vi, i = 1, . .
. , 4, associated to the indicated lines of ...
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I have a pipe connected to a 2x4 that holds a weight. How do I find the forces that will cause the 2x4 to bend?
I'm building a lumber rack similar to this, but in my case, the vertical supports (2x4s) will not lie against a wall. They will, however, be fixed at the top and bottom. I'm wondering roughly what ...
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Attempting to solve for reaction forces in a beam results in a singular matrix
I am attempting to solve for the reaction forces in the following beam, and set the equations up as an Ax=B system. Currently I have four equations for the four unknown reaction forces. Are my ...
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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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How does bearing reliability factor effect the static safety values of a bearing?
I have a SKF 30202 style bearing and i found that the static safety factor of this bearing is 2.76 for a reliability of 90% how does the static safety factor change if my reliabilty was 99%? How can i ...
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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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Stress concentration
Let's say we are using an aluminium with a yield and ultimate stress for an element like this:
In this case we will get some stress concentration around the fillet due to the change of area, however, ...
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Where does this support reaction come from?
I am looking at part a of the following question,
and I can not figure out where this support reaction N is coming from. The solution is as follows.
The question and diagram make no mention of N. My ...
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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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Equilibrium problem with 3 unknown forces | Hanging mass
This problem is related to my previous question on the generalized Lami's theorem. I would like to see how you solve this problem and compare with my solution. My motivation for this problem is that I ...
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how to determine the direction of support reactions in a truss?
Hi, I am not sure how to determine the direction of support reactions at point A and K. I know point A has a pin support, therefore, it can take in horizontal and vertical loads and point K has a ...
user38335
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Is there a way of "shortening" a mechanical lever, but keeping its mechanical advantage intact someway?
For what I think I know, the mechanical advantage of a lever comes in exchange for the distance the load travels upwards, independent from the type of lever (I think).
So, let's say, in a (class-1) ...
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Could a hybrid system of mechanical levers and hydrostatic/hydraulic cylinders be able to lift 200+ kg with the force of an arm?
I don't know much about levers and hydrostatic/hydraulics myself, so I hope I don't make too many misconceptions.
The idea:
Hypothetically, if you had a 40km+ long indestructible lever on a ...
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How to calculate forces on bearings in a chain drive
I have a chain drive which is moving a load of 200kg. I have 95Nm on the input shaft which has 15 teeth, which results in 152Nm on the output with 24 teeth.
The shafts are supported on bearings on ...
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Best way to deploy a projector screen from the bottom?
I want to design a system for an electronically deployable projector screen, where when not in use the screen is stored at the bottom and there are no structural elements sticking up significantly, ...
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Mechanism and static determinacy
I was doing exam question and am confused as to how to determine if the structure is a mechanism or not.
Say that j = number of joints, r = total number of reactions, b = number of bars.
For both (a) ...
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What are the physics behind a TV wall mount?
As I was installing this wall mount, I began to wonder how exactly physics is at work with it. In other words, how does the design of the mount play a role in ensuring that the mount itself supports ...
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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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Equations of condition: why are two moment equations around a hinge dependent?
I'm reading about static determinacy of structures here.
A quote:
Therefore, one extra equilibrium equation is added to the system due to the introduction of the hinge: either ∑MABB=0 or ∑MBCB=0. ...
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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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should the hachures in moment and shear diagram be vertical?
when we plot the shear or moment diagram we add hachures to the area created with these diagrams , in most cases we see vertical hachures, is it represent the internal forces? or its just used to ...
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Stress on a statically indeterminate beam with nonuniform temperature distribution
The bar below has length $a$, an uniform cross-section and has both ends fixed to walls. The temperature at the left end is raised by $\Delta T_1$ and that of the right by $\Delta T_2$, where $\Delta ...
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How can I justify a consistent sign convention for statically indeterminate problems?
I am watching the below video on statically indeterminate axial loading. When he makes a cut on the left half, I understand why he draws the internal force acting to the right, because if he drew it ...
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Statics Reactions
I'm trying to do this problem using components but I'm having trouble. I see no reason why I can't use this to solve. Maybe I got one of my variable wrong? Can some one help me figure out what I'm ...
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How to draw force diagrams Statics Reactions
So in class we went over the different kinds of supports and in this problem I have to determine the reactions at A and E.
When I drew my force diagram, I drew (using components) a total of 7 forces. ...
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How should I position three shelf supports for the best distribution of load?
I'd like to mount a shelf on the wall using three shelf supports. Where should I place the three supports for best distribution of load across the shelf?
Edit: To clarify, the load will be distributed ...
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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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Why does the method of joints not match a force balance result?
I am trying to figure out why the two approaches do not match in solving this statics problem. This involves the image below.
The first thing to do is to find the reactions at A and E. This is easy ...
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How do you simplify this load diagram?
Very rough sketch but I'm having trouble with a Shear and Bending Moment problem, and I'm pretty new to the topic.
This is the original diagram:
I already simplified the left side (not sure if it's ...
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What is a shear release? [closed]
For my statics project, we are being asked to draw the shear and bending moment diagram for a beam, which is usually pretty straightforward. However, here there is something called a shear release on ...
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Can the general statics theory equations be used to calculate force reactions for pinned-roller support system?
Observe the figure below.
Left end is pinned while on the right there is a roller support. The system is statically determinate, i.e. the reaction forces can be found using simple 3 equlibrium ...
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Maximum shear in a beam
Engineering books and lectures typically make two things clear:
Maximum bending stresses (normal) develop at the beam surfaces, that is, at the greatest distance from the neutral axis.
Shear stresses ...
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Modeling the Internal Forces Exerted on a Catapult Arm while Throwing
I am currently creating a MATLAB script to determine the internal forces present in a uniform beam as it is accelerated by a torsional spring. I was able to derive the equation for the axial force ...
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Method of sections - Is it compression or tension?
I know how to do the method of sections, however I get a confused once I get an answer and move on to the next section.
For example this truss. I worked out joint A, AE = -84.9 AB = 60, but when I ...
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How to find clamping force from bolt preload?
If I have a piece of rubber between two steel plates, and four bolts (at equal preload) compressing the plates, will the total compressive force on the rubber be Preload x 4?
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When we replace supports distributed reaction by point reaction in thin beams, is that considered an application of Saint-Venant principle?
I read about Saint-Venant principle which is about the effect of replacing forces by equivalent forces system that effect on the same small region of a rigid body, all examples I come across are on ...
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Help with understanding bending moment diagram of a frame structure
I have an exercise where I should calculate and draw a bending moment diagram for a frame structure. The frame structure is similar to the one below, image taken from http://structx.com:
I would like ...
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How is Kyrie Irving body stay balanced in inclined position?
How can we explain this in a scientific way? As far as I understand, your body will stay balanced if the projection of your center of gravity to the ground is still between the area covered by your ...
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Why are screw holes in most of the door hinges in zigzag orientation?
What advantage does it provide? Explaining with a figure would be helpful.
I tried to draw a free body diagram and equated the sum of force and moments to zero, but still was not able to find out.
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Utilizing symmetry in statics problem
I am given the structure below, and supposed to find the forces occuring in $A, F, E, D, C$ and $B$. The task hints of using symmetry, as several forces are equal in magnitude.
Supposedly, $A=B$, and ...
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Mechanics Statics: verifying reactions at supports
Figure (a) shows the problem and (b) the free-body diagram. The question is to verify the reactions at C and E.
I understand the remainder of the free-body diagram but do not see how C and E are ...
