Mechanism Definition and 511 Threads

Hi, This is my first post and I've joined simply to see what anyone may make of the following idea. Given the relatively recent depictions of the universes 3d structure as something akin to nodes with filaments connecting them. It seemed that the expansion of the universe could be explained by...

Hello everyone! I'm making a costume of a game character and I think I need some guidance regarding the mechanical aspect. I asked this question on a cosplay site, but they suggested I might get more help here. So I'm going to cosplay this character on an anime convention: As you may have...

I am confused about how the gauge boson W+ and W- get their charge under spontaneous symmetry breaking in the Higgs mechanism. Here's what I have so far: The covariant derivative for a SU(2)⊗U(1) is DμΦ = (∂μ + igWμiσi/2 + ig'Bμ)Φ where g and g' are coupling constants. SU(2) is associated...

Homework Statement In a charming 19th-century hotel, an old-style elevator is connected to a counterweight by a cable that passes over a rotating disk 3.50m in diameter (the figure (Figure 1) ). The elevator is raised and lowered by turning the disk, and the cable does not slip on the rim of...

Hi there! Currently i am trying to design a four bar linkage for a bicycle rear shock. You can find this linkage at here http://ffden-2.phys.uaf.edu/211_fall2010.web.dir/Michael_Stanfill/VirtualPivot.html This linkage is called virtual pivot point. Critical part of this design is to achieve a...

Does the kinetic energy of molecules make us feel a substance to be hot? I want to know the mechanism through which we feel something to be hot. How the molecules come in contact to our skin molecules and interact with them to send message to our brain through neurons? How the brain atoms...

Water is poured into two containers separately at two different rate. Will the rate of increase of water flow affects the pressure building up? Can the pressure affects the time taken for the water to overflow the container? ( One of the container is designed to avoid overflow, hence the rate...

Homework Statement I am given a four bar mechanism and the mathematical representation of a point on the coupler I am looking for ways to determine the lengths of the linkages from this information? Homework EquationsThe Attempt at a Solution I really have no idea

Hi, I need to design a lift mechanism that is powered by a small continuous servo. It needs to lift a plate up at least 4 inches, and be totally powered by this servo...

Do we have to rote memorize it or is there mechanism so that we can learn it easily? There are some ion exchange reactions which are simple like NaCl + H2O-------> NaOH+ HCl. but for example what about this? P4 + NaOH + H2O----> ?

The overall reaction for the formation of phosgene from Cl2 and CO is: Cl2 + CO --> Cl2CO The mechanism is: Cl2 + M <--> 2Cl' + M Cl' + CO <--> ClCO' ClCO' + Cl2 --> Cl2CO + Cl' For this mechanism, the sum of the elementary reactions is: 2Cl2 + CO --> Cl2CO + 2Cl' However, doesn't the sum...

I'm looking for a simple latch design. My project will have two roller chain sprockets positioned one above the other with about a two foot gap. A motor will turn one of the sprockets and the other is just an idler sprocket. A #40 roller chain will run around the two sprockets. Mounted just...

What is the mechanism of trinitration of phenol ? Is it one by one substitution of nitro groups ? For which wouldn't the nitro groups stop the reaction as they are deactivating groups Or is it the simulataneous activation of ortho and para positions of phenol and the nitro groups add on...

I'm trying to design an entirely mechanical system for returning an extension spring to its extended state, without the assistance of electronics, pneumatics, hydraulics or any other form of auxiliary power. It's for a soft exosuit concept that simply enhances the speed and ease of walking or...

Hi all, I think it's just an Eigenvalue preoblem. I'm studying Seesaw mechanism from http://www.quantumfieldtheory.info/TheSeesawMechanism I don't get how he substituted in equ. 21 for N Eigenvalue from equ. 20, that ## \frac{m_D}{m^R} ## is a factor of ## \nu_R ## not ## \nu_l^c ## ? Any help ..

I'd like to know the physical mechanism of oleum "fuming" on its surface. Dissolved SO3 reacts very exothermically with some air humidity. Why does the mist occur instead of dissolving created H2SO4 in the solution?

Homework Statement The rate law for the reaction is found from experiment to be Suggest a mechanism consistent with the rate law. Homework EquationsThe Attempt at a Solution Here is the webpage with the solution http://www.umich.edu/~elements/07chap/frames.htm Here is the solution Rate...

Hi guys and girls this my first post! Hope i got it in the right place. I need help understanding the mechanical advantage of this mechanism. The top sprocket is the input power the bottom sprocket is an idler the attachment on the chain is the output. Help!

Homework Statement Problem: I am told that the first mechanism is operative in saponification. The Attempt at a Solution However, this strikes me as wrong because the first mechanism involves the formation of dianion. Using hydroxide ion to abstract a proton and make that particular...

how does d-d transition take place when there are no free higher energy level d-orbital's left(as the only two higher energy d orbitals form coordinate bond with CN-?

Homework Statement Rod AB rotates with the angular velocity and acceleration CCW as shown. Points A and D are pin connected. The collar C is pin connected to the link CD and slides over the link AB. At the instant shown the link CD is vertical and the link AB has an angular velocity of 2 rad/s...

I need to obtain the forward and inverse kinematics of a pantograph device. It is easy when only the one side of the pantograph is considered; So, it becomes a 2DOF planar elbow mechanism, which is easy to solve. However, there is symmetry on pantograph, so I kinda need to combine two planar...

Please see the above picture, I need a mechanism to connect handle to a controlled object below. While the handle moves from a to b (~10cm) the object needs to move from c to d (about 25 - 30 cm) and when handle moves back from b to a, the object needs to moves back from d to c. They are both...

Homework Statement This was a lab. I started with Maleic Acid. We performed a temporary corbonication to see whether or not the single bond would rotate to create fumeric acid, maleic acid or both. The question that I have to answer that I cannot answer is: Explain the mechanism of the...

Hi, I'm working on a project, the project is to create a ball launcher. the ball being a squash ball. 3 balls must be loaded once only but be able to be fired individually. the energy used to fire these balls is 3 1m long bungee chords. this cannot be changed. there are 3 main parts to it.1...

Greetings I don't know if this is the right place to post this because I'm not certain how it is classified or if it can come under many headings. So please move this if it is better suited elsewhere. I watched a video on pbs.org a few years ago and since I am just now writing here about...

I understand that Higgs mechanism “gives” mass to particles in QM sense. My first question is, why it also gives mass in GR sense, bending space-time? Of course, I don’t expect an answer now as it is definitely a TOE/Quantum gravity territory. However, let me rephrase my question in a narrower...

Hello all, I am trying to design a system with a sensor that can detect when an inflatable is inflated to 2 PSI. I am trying to inflate something small, around 6 liters. I currently have a system that uses a solenoid, the compressed air, and a mechanical timed relay that tells the system when...

tert-butyl bromide + MeOK in MeOH -----> I would think that MeOK would dissociate in solution making it MeO- which would be strong enough to yank a proton off tert-butyl bromide and initiate an E2 reaction. Where am I going wrong? PS - I am a tutor who hasn't done organic chemistry for a...

Hello. Since the Higgs Boson is responsible for giving sub-atomic particles mass..or any particles there mass..is there a present understanding of the mechanism by which the field actually does this? And if there is...is there any artificial way of controlling it? My thinking is that if you...

I am not well versed in the idea of Higgs mechanism. However, I was wondering if it does explain the problem of equivalence of gravitational and inertial mass. Also, what is the modern accepted definition of mass?

Hello, I read about airfoil mechanism that there happens to be pressure difference created above and below the airfoil which result in lift force. My questions are: 1. What actually happens in the speed of air. I mean how can one side of the air travels with greater speed when they have the...

Hi, I have been trying to find all the retraction mechanisms possible to bring the nut back on the threaded shaft when it comes forward. Constraint is geometry. Between the back of nut and the face of the threaded shaft, space is max. 6 mm. also, the nut moves only 2 mm forward on shaft...

I'm a mechanic and I'm debating the exact mechanism of the so called "pumping losses" or "pumping work" of conventionally throttled 4 stroke spark ignition engines. We know that EGR is employed to reduce intake pumping losses and actually increases engine efficiency for slightly better fuel...

Hello, I bought an electronics kit for my 12 year old brother (and perhaps a little for myself too...) for building a crystal radio. I would like to understand what's going on when I tune the radio, so that I can explain it to him. It's a simple setup, where changing the position of a...

On many boiler feed-water systems there are deaerators which essentially sparge steam through the water. Why does steam deaerate water? Is this simply a temperature effect on gas solubility? Or something else?

I'm just looking for a layman's explanation of why the efforts to confirm Higgs was truly necessary and worth the expense. The counter-argument is that theoretical physics seem to be going along just fine assuming something like the Higgs mechanism existed without validating it. Also, nothing...

http://iopscience.iop.org/1748-9326/9/5/055004/article http://www.bbc.com/news/science-environment-27406358# Activity on the Sun is sparking lightning strikes here on Earth, a study suggests. The finding was surprising, said Dr Scott, because it had been thought that an increase in the...

If a neutron is unstable outside the nucleus, then what makes it stable within the nucleus? Does the binding of particles together somehow make them stable? Neutrons decay via the weak force, but are bound in the nucleus by the strong force. Does the strong force inhibit the weak force...

We all know that Einstein's theory apply to the big universe, and quantum mechanism apply to the nanoscopic scale, and both theory work perfectly in it's realm, but how could two theory contradict each other?

I have some questions how various substituents are transfering benzene conjugated (π) electrons (i.e. activating/deactivating). As usual, no chemist provides an explanation. 1)As I see, the first important thing when forming a carbocation during electrophilic aromatic substitution is to find...

Hi there! There is a technique that is being used by my lecturer for mechanisms course at uni and i could not understand how this technique is manipulated.I wish i would know this methods name but no chance!. This technique is being used to find normal acceleration of link in 4-bar...

Let's suppose that we have a rod which is 2 meters long in its rest frame. Its rest length can be defined as a set of points which do not occupy the same place, measured in a frame which is at rest with the rod as a whole. Now if we travel relative to the rod, it gets length contracted, I...

Homework Statement This is a mechanism I'm working with for my undergrad project (its Modelled in Msc ADAMS) https://www.flickr.com/photos/35430110@N04/13902494524/ https://www.flickr.com/photos/35430110@N04/13902494524/ And to give you an idea of how it operates; position 1...

Newton second law of motion states that acceleration is produced when a force acts on a mass. The Higgs field (mechanism) is the cause of fictitious forces?

I think that our current knowledge on the initiating mechanism of supernovae is that they happen due to neutrinos interacting with the inner layers of a star and then accelerating them away from the core. I am having some trouble in understanding that idea. Of course this could be plausible if...

Hello folks, I have very little robotic experience, so would like to start my knowledge accumulation here at PhysicsForums. I am trying to design and build a launching mechanism to launch a 400 gram projectile. I was hoping to get a bit of guidance in what devices I should be looking into...

We know that water rises in a glass capillary owing to the surface tension phenomenon. If we make an arrangement as shown in the attachment, (read Water instead of mercury in the attachment, I got confused there) & do the following procedure. The valve at the bottom is open, & the one at the top...

how can we determine the loops in this mechanism.

Hi, What is the molecular-level mechanism of shear-thickening of oobleck (cornstarch-water paste)?