Mechanism Definition and 534 Threads

Take the first family of fundamental fermions, u, d, e-, and ν. The u and d are more massive than the e- and the e- is more massive than the ν. The u and d interact via 4 forces, the e- interacts via 3 forces, and the ν interacts via 2 forces. The fermions that interact via the most forces are...

Dear @ll, the central point (for the unitary gauge) in the higgs-mechanism is the equality Φ = (v + η + iξ) = (v + η)ei(ξ/v) (see for example Halzen, Martin: Quarks and Leptons, eq. 14.56) Φ = complex scalar Field v = vacuum that breaks the symmetry spontaneously η,ξ = shifted...

As medulla is hyperosmotic with respect to medullary collecting tubules (I.e. main site for water absorption )water flows out of the collecting tubules and urine get concentrated ...But how it enters vasa recta since vasa recta is also going through same hyperosmotic medulla ,how it absorbs...

Hi, I'm new to the forum and I am after some help to blow the cobwebs regarding a leverage problem I have, I am a draftsman and did structural engineering diploma many years ago that had limited statics and dynamics, I have forgotten all of it... In a nut shell we have a working model of both...

Homework Statement I have a question asking me to find the launch speed of a ball (mass 0.39kg) when released by a spring mechanism made of 2 springs each with force constant 25Nm^-2. they are pulled back 12 cm. the ball is initially at rest.Homework Equations [/B] v^2=u^2+2as f=ma f=kx...

Homework Statement Viewing a solution on the internet to this question, the free body diagram is drawn as: The forces here are then used to solve for ##F_D## and this is given as the answer to "the force which the bar exerts on the link at D". I'm just confused as to why there is no...

Homework Statement A four bar chain is arranged as the diagram shown below If the input link AB rotates at 400 RPM anti CW determine the angular velocity of link DC Homework Equations See attached photo The Attempt at a Solution See attached photo

Recently I heard that NEFFUL clothes, when rubbed with our skin, could release anions (refer to attached image for more details). I do not doubt the generation of anion, due to Triboelectric effect. But could anyone advise, where does the "cations" that were produced during the ionization go?

Please excuse my poor explanation in advance, I'm not an engineer. I have a latching mechanism that has an off center piston and needs to get actioned from a 'cantilevered' position. Please see attached (crappy) sketch of desired effect vs real world behaviour. Is there any solutions to negate...

There is something that perflexed me. First here are the references to my questions: http://www.latticeguy.net/mypubs/pub017.pdf http://bose.res.in/~bossar/chandu.pdf What I'd like to know is the following: Without superstrings. Quark confinement and asymptotic freedom says as you pull the...

I'm familiar with the Higgs mechanism.. but what perplexed me so much is the temperature dependence. I know about superconductivity or magnetic-temperature analogy.. or generally I understand what's written in wiki https://en.wikipedia.org/wiki/Higgs_mechanism "Below some extremely high...

I'm looking for a simple explanation or decent analogy whereby something that is symmetrical and smooth like a black hole or even a spinning neutron star can drag spacetime as if spacetime was a viscous liquid. It guess it might make sense to me if gravity was unified with EM. I can see how two...

Hi, I was wondering if there is a mechanism to explain how the strong force leads to an energy release when two light nuclei such as hydrogen fuse together. I get that the products of fusion have less mass than the reactants and that this "missing" mass is converted into energy in accordance...

I have been struggling with this problem for a long time now, and are hoping you can help me. The assignment was to design a mechanism for opening a window with less effort. My way of solving this is to store energy in a spiral torsional spring as the window closes, which would be released when...

Good afternoon guys, I want to discuss with you guys a few things... So i already design a log cutting mechanism as you can see in the picture below. But there is so much defect on my mechanism.. The biggest thing that stressed me out, its still uneasy to use because after cut the log, the user...

Good morning guys, So i want to make mechanism to cut log with diameter 5 cm and 120 cm length. So how i can calculate the force to cut this log perpendicular and paralel. What is tbe formula i can use? And how i can determine the saw thickness and rpm needed to cut this log? Thanks guys for...

Hallo all, I'm investigating in using a dieletric barrier discharge for gas treatment, if I have two electrodes isolated by dieletric and the discharge gap between both of them has AIR.. how the ionization of air will take place, from where the source of electron which is going to start the...

In Quantum Field Theory, I am led to believe that there is a different field for each type of particle. When particles interact, it is an exchange of vibration between the fields. What mechanism is at play when one field influences another in this way? It seems I've only ever found...

α decay probably implies that heavy enough nuclei which undergo this decay, consist relatively loosely bound α particles and extra neutrons. I haven't found any theory which views nuclei in this way. I value truth in science, and would like to know it, also regarding stucture of nuclei and...

Homework Statement In the figure, a piston P is connected to a cylinder. The piston is connected to a rotating wheel with two shafts AB and BC. The shaft AB is connected on the periphery of the wheel. The wheel is rotating with angular speed ω= 100 rad s-1. At the moment A,C and the center of...

Hi. I'm searching for a name of the spring mechanism that snaps-up and snaps-down this type of Switch cover https://cdn.sparkfun.com//assets/parts/6/9/9/0/11310-03a.jpg . on the left side of this red cover, you can clearly see the spring and few other things, that makes it to resist any change...

Hello, I am high school student working on a project to design an air cylinder, which would fire seed pellets from the drone at specific time intervals with sufficient pressure to embed them into the soft soil. I looked up on the Internet about airguns and other stuff but couldn't find...

Does anyone know if the following is available as an off-the-shelf component and what would it be called? One-way rotation mechanism Has detents or stops at specified intervals (such as every 90 degrees) Fairly small - for attaching an approximately 2" diameter wheel or circular disc to Doesn't...

Hi all, How does matter curve space (what's the mechanism)? Does this Curvature happen instantaneously or does it happen at light speed? Thanks in advance.

I'm not sure if this is the right thread to post this, but here it is! I'm currently trying to create a prop for one of my friends, since I found it an interesting challenge. This is a simple drawing of what I'm trying to do: The button, battery and so on it not my problem, it's that I've no...

Hello, I understand how evaporation contributes significantly to heat loss through the loss of KE from the vibrating water particles on the skin; However, what about the sweat droplets that come off of a person. This water has Kinetic Energy and is now being displaced from the body(the...

I would like to ask for somebody to point me in the right direction - any literature I could read - regarding the mechanism behind color changes that an organic solution undergoes due to changes in pH. I am not referring to organic indicators or dyes, specifically. I have observed in my...

Can anyone help me in what they think would work as far as placing a locking mechanism on a watch band?? I need it to lock onto the wrist. So it can not be taken off by the wearer. I do not want it to need any type of key or source that can be lost. I have been recommended a bluetooth type of...

Homework Statement The brake mechanism used to reduce recoil in certain types of guns consists essentially of a piston which is attached to the barrel and may move in a fixed cylinder filled with oil as the barrel recoils with an initial velocity v0, the piston moves and oils is forced through...

hi guys solar activity has been a love of mine since the early 1970's and am always looking out for new research info :smile: some recent studies and lots of computer animations have come up with new understandings of the mechanisms that instigate CME's and other mass ejections from the sun...

Hi, I wanted to make a locking mechanism. The problem was the forces on the actuator (solenoid in this case) where getting too high In image 2, the wedge shaped lock plate was exerting too much force on the actuator, which would unlock and could potentially break the actuator. Or I would have...

I know the seesaw mechanism is a model used to explain both neutrinos having mass and why their dirac mass/yukawa coupling is so much smaller than for the other fermions. The seesaw mechanism needs the right handed neutrino to exist. How does the seesaw mechanism for the vMSM differ from that...

Hi there So we have a group design project in my mechanical systems 2 class and it basically goes as follows: design a mechanism to cut a half inch aluminum bar in half using a standard hacksaw blade and 4 AA batteries. You have to use a motor w/ input > 5000 rpm for the 'main' component we...

So the Supernova is something that results from a radial bounce somewhat akin to the stacked ball drop, where the momentum is transferred out radially. But GRBs are said to have happened from accretion disks. So a rapidly rotating star that rotates fast enough should flatten out the star...

Hi I am trying to make a CAD model of something like the scoop sampler shown below. http://www.rolls-royce.com/~/media/Files/R/Rolls-Royce/documents/customers/nuclear/scoop-sampling-tcm92-50918.pdf This is for a university coursework that requires design of bespoke machines. I am trying to...

1. Homework Statement An iodine clock kinetics experiment was performed by varying the composition of reactant solutions and measuring resulting rates of reaction (based on the data given, I have determined the rate law to be R = [I-]1[S2O82-]1). Which of these four proposed mechanisms below...

Hi all, I sputtered titanium (10 nm) - gold (~ 100 nm) films at room temperature on oxidized silicon substrates. The titanium acts as an adhesion promoter between the SiO2 and the gold film. My Question: What is the adhesion mechanism between the titanium and gold film at room temperature...

I want to determine the natural frequencies and the mode shapes of the given mechanism ( it consists of 2 inclined beams connected together by a compliant link, the bottom end is fixed and the upper end is a roller support). I have done Finite element modeling but I need to get some analytical...

Hi, I would like to understand what is the MΔ which appears in the neutrino mass mechanism with Type-II seesaw. It seems to be the Higgs triplet mass. But I do not understand what is (physically) the masse of this triplet when we define it with 3 components : Δ=(Δ++,Δ+,Δ°). It is different from...

I am currently re-fabricating solar concentrator dishes to allow for automatic tracking of the sun during the day and month. The industry term for these dishes is 'CSP' (Concentrated Solar Power). Task at hand: The CSP parabolic dishes are currently manually adjusted to the position of the sun...

Hi all! I'm new to this forum and, as a matter of fact I only recently rediscovered my interest for physics. I am starting to catch up, yet I find that Wikipedia sometimes falls sort for some basic questions, and I was hopping that this community could gently help me understand some concepts...

Hello guys, I have a doubt with understanding DOFs. I have taken the example of the four bar linkage. According to Grueblr's condition, the DOF of this mechanism is 1. \mbox{DOF} = 3(l-1) + 2j_1 + 2j_2\\l=4\ j_1=4\ j_2=0\\\mbox{DOF} = 1 In the above figure, the links next to the ground link...

I am working on a mechanism which controls the release of energy while remaining energy efficient. An image of the concept is shown below. (The image is meant simply to get an idea of how it would work- it is by no means perfect). A source of energy (from a spring being released, for example)...

Homework Statement In the speed-governing mechanism m = 0.2 kg, L = 10cm, (rods AB have negligible mass), w = 500 rpm, θ = 40°,θ' = 0 . Determine θ'' at that instant and the tension in the rod. Homework Equations F=[ω][/2]rThe Attempt at a Solution First, I calculated ω = 500 rpm * 2π /60 =...

My professor explained to us that the purpose of a zero-force member in a truss is to increase the stability of the truss during construction, to provide added support if the loading is changed and to prevent the structure from becoming a mechanism. It is this latter point that I do not...

Hi, I want to apologize in advance because I have not studied mechanical engineering in any profound sense other than in my hobbyist projects (I focus more on software engineering). Currently I am creating a real life Raspberry Pip Boy 3000 MK 4 from the Fallout 4 video game with instead of...

1. Homework Statement 2. Homework Equations rate law equation 3. The Attempt at a Solution a) I would expect this reaction to be a multi-step reaction because there are six reactant molecules, as shown in the overall chemical equation. For this reaction to be one-step, all six molecules...

The situation is part of a mechanism I have been working on. It is used for a bicycle to automatically store and release energy with a spring. It is somewhat similar to a car clutch. Homework Statement Two friction discs are rotating with different angular velocities and different torques. The...

Hello I'm looking for a graphical software to simulate a gas sensor mechanism. I thought "comsol multiphysics" could help me to determine the sensing mechanism of semiconductor gas sensor , but I didn't find any thing about this. I would appreciate you If you recommend an appropriate application...

I have an assignment in which I must find a named reaction, the original reference to it, and show what experimental evidence was used to develop the reactions mechanism. So far I've had no luck finding anything. It's hard enough finding the original reference and so far I haven't been able to...