Vibration Definition and 429 Threads

< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown >[/color] Okay, I am having trouble with the units. I have the values for the wavenumber and I am trying to find the period. These are the formulas that I am trying. T = 1/f ; f = c/lambda...

Hi, I have previously made a post in order to gain some insight in my rather out of control project. Long story short I am investigating vibration of a circular plate and its standing waves. After consultation at this forum I have been guided in the direction of acoustics and bessel functions...

So, here's the set-up: A small stereo speaker is connected to a function generator. A concave lens, bearing a ball is place over the speaker. Now, the frequency is slowly increased in the function generator. My question is, Will the ball really bounce at a certain frequency? Because I am not...

Hi everyone. I'm wondering if vibration (likely acoustic) could be used to achieve a uniform suspension of an insoluble solid within a liquid solution? It seems completely reasonable to me, but I'm unable to find any information on the topic. I'm planning on getting in a lab to test it soon. Can...

I've found several accelerometer apps for smartphones (for example http://www.iseismometer.com and http://www.now-instruments.com/products/3-vibsensor ). Are these useful for doing quantitative vibration analysis, and if not, what are their deficiencies?

Hi guys, I'm new to this forum and this would be my first post :-) Hope you guys can guide me on what to do on this alternator that's having problem with vibration. I'm running out of ideas now on what to do with this alternator. The alternator was sent to our workshop by the client for...

Homework Statement three harmonic function of frequency p, 2p ,3p were added together. what is the frequency of resultant periodic function? Homework Equations X=Asin(wt) A-amplitude w-frequency X=X1+X2+X3 The Attempt at a Solution need a hint ..

Hi There, I have a VTS(vibration test system)-100 shaker. To make sure it works correctly, I have done a acceleration frequency response test for the bare shaker. In which, I place an accelerometer on the top of the shaker platform, use a function generator and amplifier to drive the shaker at...

Just a general inquiry, and not for any personal gain and or theory, I would like to know if anyone has developed a formula for measuring the vibrational rate of an atom.

Homework Statement Rigid body with one spring. Homework Equations Torque equations ( M=I * "alpha") The Attempt at a Solution So I think I can solve this problem but there is only one thing I do not understand. When I am writing my torque equation I would think that the weight of the bar...

Homework Statement A half-full water tank mounted on the top of a building is modeled as shown below. Find the shear force it can produce? m = 500 kg k = 1000 N/m model: https://app.box.com/s/qke2kbwag2mp9a23kkqq Homework Equations Transfer Matrix Method: Point & Field Matrices...

Homework Statement http://i.imgur.com/wJu0AEs.jpg http://i.imgur.com/J9sEWgq.jpg?1 Homework Equations Kinetic Energy = T = 1/2 * I * (theta_dot)^2 Potential Energy = V = 1/2 * Kt * theta^2 The Attempt at a Solution Matlab Code and Results: >> I1=3600; I2=200; I3=800; I4=4800; d1=0.15...

Hello everybody , I am student in mechanical enginnering. I have to evaluate the solution Fe-Safe. i am working on two subjects: Harmonic and PSD Vibrations. The modal analysis are done in Abaqus. I would like to understand how Fe-Safe computes Life Fatigue in case of harmonic analysis. What...

Hello, I am studying and trying to understand Powertrain / Engine mounts used in automotive such as these: http://images.gasgoo.com/MiMwMDRfMDA0Izc4MDA3NzIwMA--/auto-part-engine-torque-strut-mount-engine-mounting-for-buick-enclave-chevrolet-traverse-gmc-acadia-25840458.jpg...

Homework Statement y(x,t) = (9.00cm)sin((5Πcm-1)x + (3Π rad/s)t - Π/8) There are 11 parts, and I have answered the first 10 (they include velocity of a wave, amplitude, all that good stuff), but I haven't seen anything in lecture or in the textbook that mention finding maximum vibration speed...

Homework Statement a.) Find the total energy of vibration of a string of length L, fixed at both ends, oscillating in its nth characteristic mode with an amplitude A. The tension in the string is T and its total mass is M. (HINT: consider the integrated kinetic energy at the instant when the...

Can somebody please tell me what should be present in the free body diagram for this system below. Also please mention the arrow details like which direction each force in the free diagram should be acting in. I really need to understand this concept...

Let us imagine that there is a Massless spring with fixed at one end. Unloaded length = L Spring constant: = k Mass = 0The spring is at static Equilibrium Force: F Displacement: d F = k d, elongated length: L+d If I remove F, what will happen ? 1. Spring return to...

Hello! I want to ask about spectrum of Ac induction motor, first of all, we measure points at non drive end + drive end - radial+axial direction. At horizontal direction we measure not only velocity but also acceleration. Two questions: 1. I see a peak around 65000 rpm with sidebands at...

So the equation to obtain the frequency of the modes of a square membrane is something like ω m,n = ∏ [(m/a)^2 + (n/b)^2]^(1/2) This equation can be used to get the frequency for Modes such as (2,1) and (1,2). How do I get the frequency for such modes as (2,1)+(1,2) and (2,1)-(1,2) ...

Why are we not supposed to operate a machine on its natural frequency condition? I read max. energy transfer happens at this condition. What exactly does it mean? When we swing a pendulum it just oscillates on its natural frequency. Nothing goes wrong there. So what makes it different for a...

I've just got a quick question that hopefully someone can answer. My question is - why does the membrane in COMSOL vibrate without you telling it to? Here are some specifics if required... In COMSOL here are my setup details: - Physics: (3D) Structural mechanics - Membrane Study...

Hi Folks, I am trying to replicate a solution in Matlab for the following problem ##\displaystyle \ddot x + \frac{k}{m}x = \frac{F_o}{m} \sin w_ot## using 2 first order linear differential equations in Matlab as shown below tspan=[0 4]; y0=[.02;1]; %Initial Conditions for y(1)=x and...

Homework Statement I'm following a procedure in a particular paper as part of my Masters project. The paper is called 'Theoretical investigation of the sound attenuation of membrane-type acoustic metamaterials - Y Zhang, J Wen, Y Xiao, X Wen and J Wang (2012)' and can be seen...

Hi, So basically I am wondering how can you increase damping within a part, just by altering its geometry. I've researched this topic, but haven't yet found anything significant. Here are my main findings: - Rayleigh Damping uses the equation: [C] = α[M] + β[K], which to me shows that mass...

Hello all, I'll start by explaining that this is my first post, and I have very little engineering and mechanical knowledge. I am currently completing my phd in neuroscience so the purpose of this post is to seek information to indulge in some of my hobbies :) I am designing a machine...

dear all, I am working on a problem about the vibration of a piezoelectric ring with electrodes on the upper and lower surface. the coordinate system is cylinder coordinate system. the structure is shown below. This is an axisymmetry problem. the polarization of the piezoelectric ring is...

Can anyone help with the following - which I have been musing about for some time. mThe general idea is that when heat is applied to a substance the molecules / atoms in that substance vibrate more and more (until the bonds in the molecule break). OK - so can anyone help with the following...

BTW, exist some substance that when is mixed with nitrogen, or with some compost of nitrogen, reacts and explodes? Also, exist some compost of nitrogen that when is submitted to high vibration or shock reacts and explodes?

Homework Statement A liquid (density ρ) is poured into a bent tube such that the two halves of the bent form angles α and β with the horizontal. The length of liquid column is l. If one of the liquid levels is depressed and released, the levels begin to vibrate. Find the period of vibration...

Good Afternoon, all... I design professional pitching horseshoes. I am trying to determine if the method used to mount the stake in the horseshoe pit affects the recoil of the stake when a horseshoe hits it. A stake that loosens over time will reject a horseshoe more readily than a solidly...

What does a first / second / nth order frequency mean physically?

Hi, I'm currently studying Mechanical Eng & have a class next semester 'Eng Analysis', which involves a large section on vibration. I've been trying to work my way through S.S.Rao, Mech Vibrations, 2nd edition. There's one specific problem; Project 5.51/Chapter 5/page 292. The problem concerns...

Homework Statement Middle C on a finely tuned piano vibrates 262 times per second. What is the period of the wave? Homework Equations T =1/f The Attempt at a Solution Im just really confused.

what is the difference between vibration, oscillation,simple harmonic motion and periodic motion?Is there any similarities between these terms? can anyone explain clearly pls.

I am doing a project in controlling the vibration in 4 wheeler exhaust system by using dampers. But i am not sure of what kind of dampers to use. Also is it possible to add multiple dampers and one just near the exhaust manifold.

Hi there! Just as a disclaimer before I start: I am new to physics and new to these forums, so please be kind if I say anything that seems silly to those who know more than me on the subject. :) I've been looking at this old thread about the human body and frequencies, linked below, due...

Say I have a mechanical device like this one: If I plot the acceleration profile at (trace-) point D I get something that looks something like this: Now, here's the question: Can I build a device composed of one of more (eccentric rotating mass) vibration motors that when rotating...

Hey guys, I'm working on solving a problem of figuring out what an impact velocity is going to be roughly. The numbers seem very small to me though so I was wondering if you guys could check out my work. This isn't a homework problem, but rather a real problem. I"m trying to build a test...

Does skin vibrate at the molecular level? If so does it have a steady frequency? If so would it be possible to use a laser to detect said vibration from a distance?

I need help in below matter. During the classes on my college we used this type of testing stand with force gauges : http://www.qualityforcegauges.com/force-gauges/ Unfortunately the exam is coming in strides and I still don’t know how to measure the vibration frequency. So I’d like to ask you...

tonequester here. Greetings to ALL. I have posted about acoustic resonance on my last couple of posts, and have been given much good info. I have one more post concerning concerning this topic.. I am going to do an experiment to find out the answer to my query, IF there is no definitive...

Noise & vibration in condo - HELP! Hi there, I just bought a newer condo (5 years old) and have noise and vibration coming from the mechanical/boiler room located on the first floor beneath my unit. The property manager has had a plumber come into put dampeners on the pipes, and moved the...

Hi, I am training to be a Building services engineer. I have come across a problem where I have to calculate the vibration from the generator and the transformer to the striation of the building.. how should I do it?

I am working on a motorcycle dynamics problem. I have written the equations of motion in matrix form in MATLAB (and mathcad). It is a 4 degree of freedom system, so I have a mass, damping and stiffness matrix all 4X4. I am able to find from these matrices the natural frequencies, and damping...

Molecular Vibration... I'm not sure if this is a Chemistry question or a Physics question. Please take time to correct me if I have posted in the wrong area. How do you find the frequency which a certain molecule vibrates? Like Melanin, or Serotonin, or Insulin. My brother and I are...

Does amorphous solids support phonons or nomal modes of vibration.?? Can we apply the concept of phonons and Debye Model in case of amorphous and poly-crystalline solids?? http://en.wikipedia.org/wiki/Phonon http://en.wikipedia.org/wiki/Debye_model The links I have attached above...

the heat causes the molecule to vibrate.how does the molecule vibrate in terms of angle formed by vibrating molecule and the direction of tranfer of heat in conduction, convention and radiation?

In forced vibration, amplitude of vibration changes periodically. Is it right ? I think it is a correct statement, since the amplitude of vibration is a periodic function.

according to Einstein all atoms in solid vibrating with the same frequency , while in the Debye's mode there are a band of frequency i.e not all the atoms would have the same frequency, my question is that , that is the idea behind the Debye's model? or why the frequency of vibrating of atoms...