Vibration Definition and 475 Threads

Homework Statement i want to check out which material of pipe vibration level higher . comparison between pvc pipe and nylon pipe. nylon pipe is more soft and flexible than pvc pipe. which one vibration more ? Homework Equations The Attempt at a Solution

Hey guys, I was wondering if anyone could point me in the next, correct direction for this problem. I understand how to determine the mode shapes and the natural frequencies of a cantilevered beam without a tip-mass, but adding the tip-mass baffles me a little bit. The boundary...

Hi, I'm playing around with ANSYS to find the modes of vibration of a structure. How do I know which are the most important modes? I understand that there are infinite modes of vibration - getting higher and higher in frequency. I'm guessing that it has something to do with the effective...

I'm working on an analysis problem using Abaqus. I would like to compare my results with an exact equation. My problem is modeled as a simply supported beam with a lumped mass at the end. The equation that I'm using for the exact solution is as follows: k=3EI/L3 ωn=\sqrt{k/(M + 0.23m)} How do...

Homework Statement So I have this question given to me, basically there is a aero simulator which makes the ground shake so the data logger gets false readings, now to solve this problem a vibration absorption system has been added. Please see the attached System A.png file for the complete...

Hi, i am currently doing a simulation of rotating propeller using ANSYS Workbench v13. May i know how to obtain vibration data? coz i only able to obtain stress, strain & etc for solution.. I am currently using static structural analysis only. Do i have to use random vibration analysis?

Hi, My problem is that I have 2 cantilever beams (rectangular cross section beams) placed next to each other. I want to do the modal analysis for 15 modes using ansys for these 2 beams and I also want to know how each beam is intercting with each other.CAn anyone tell me how to do this. you can...

Homework Statement I'm trying to solve an example in Boas's book (Mathematical methods in the physical science page 423) but by using Goldstein's (Classical mechanics) method. The mechanical system consists of 3 springs (with constants k) and 2 masses (with mass m) this way: |----m----m----|...

Change in guitar string tension - Please help? Homework Statement A particular guitar string is supposed to vibrate at 220 Hz, but it is measured to actually vibrate at 225 Hz. By what percentage should the tension in the string be changed to get the frequency to the correct value? Do not...

Hi, So I'm on a work term during a semester off at school (Mechatronics), and have been asked to see if it is feasible to replare some concrete plynths with steel. These are used to support a motor and, possibly, some excentrically rotating masses. My problem is that I don't really know...

A computer model has found geometries and frequencies associated with various vibration modes of my cantilever (see pictures). The model only accounts for an anchor at the far end and material properties of each layer. In reality the bottom layer is piezoelectric, it is glued to the glass top...

We have a vibration from a transmission that is showing up in some machined parts. We know the transmission needs to come apart but will need to schedule it for this summer. Has been this way for years. We need to find a quick remedy to at least reduce the problems. Transmission already sits...

Homework Statement A flexible wire 80 cm long has a mass of 0.40g. It is stretched across stops on a sonometer that are 50cm apart by a force of 500N. The wire may vibrate at the following frequencies except one. WHich one? a. 4000vib/s b. 1000 vib/s c. 3000 vib / s d. 1500 vib/sHomework...

Homework Statement A cyclindrical pipe of length 29.5 cm closed at one end resonates with a tuning fork of frequency 864 Hz. Then mode of vibration of air in the pipe is(Velocity of sound in air=340m/s): The attempt at a solution V=Velocity, n=Frequency If l1 is the first resonating...

Hi all, I have a question about Multi DOF vibrating systems. For free vibration of undamped MDOF systems, we have the equations of motion as : M \ddot{q} + K {q} = {0} (1) Where, M - n x n mass matrix K - n x n stiffness matrix {q} - n x 1 vector of generalized coordinates Most vibrations...

Hey, could anyone explain how you would preform a sinusoidal test on large vehicle (weight>40 tons). I have a graph from sinusoidal data, but i don't understant how they were able to obtain this information because there is not a powerful enough testing device.

Is it possible to weaken the bonds of H2O with by inducing a specific vibrational frequency? This idea had been rolling around in my mind for years. My thought is that if the bonds could be weakened by less energy then electrolysis alone it may become economical. I realize that some research is...

Lets us say we are doing a vibration analysis of a structure with cyclic symmetry In very brief (as pointed out by AlephZero in one of his excellent reply) the whole motion can be represented by complex numbers which describe the motion of one segment. Now, my question is: 1)Is it...

Homework Statement I wonder where can I find the definition of vibration if it was defined in quantum physics. I need it for my art written work, for Abstract artists - pioneers of modern art were researching vibration through Theosophy teachings and I would like to offer more definitions for I...

I have a damped forced vibration problem. Most problems I have dealt with have a constant amplitude sinusoidal force such as F_0sin(wt). Let's say you have an applied force that decreases each second at a constant rate over 11 seconds. It looks like this: F=0.5*[(11-t)sin(2*pi*t)+(11-t)]...

Homework Statement I have a damped forced vibration problem. Most problems I have dealt with have a constant amplitude sinusoidal force such as F_0sin(wt). Let's say you have an applied force that decreases each second at a constant rate over 11 seconds. It looks like this...

I'm working on a problem that has forced vibration. The force, every time it is applied, is less than the previous impact. For clarity, the problem is dealing with a mining skip that is emptying. The inside of the skip is separated in sections using ribs but the top blocks still exert a force on...

I'm working on a problem that has forced vibration. The force, every time it is applied, is less than the previous impact. For clarity, the problem is dealing with a mining skip that is emptying. The inside of the skip is separated in sections using ribs but the top blocks still exert a force on...

Homework Statement An air compressor of mass m1 = 150 kg is mounted on a spring of stiffness k1= 3000 N/m. The measured displacement amplitude X1 = 0.0002 m at the operating speed of N = 1800 r/min. If an undamped isolation system with mass m2=12 kg and a natural frequency w2 = 105 rad/s...

Could someone tell me what are the factors needed to be looked into before selecting Anti-vibration mounts. Regards.

If water is hold inside the water bottle, which is made of plastic, and I play music within the room, can the sound vibration get through the plastic bottle and transfer it into water? Does anyone have any suggestions on what kind of materials to hold the water to get the best transfer rate on...

Homework Statement A mass of 0.3kg is suspended from a spring of stiffness 200Nm-1. If the mass is displaced by 10mm from its equilibrium position and released, for resulting vibration, calculate: a) the maximum velocity of the mass during the vibration Homework Equations Angular...

Homework Statement A mass of 0.3kg is suspended from a spring of stiffness 200Nm-1. If the mass is displaced by 10mm from its equilibrium position and released, for resulting vibration, calculate: a) the frequency of vibration b) the maximum velocity of the mass during the vibration c) the...

I developed a COMSOL model and calculated the first 6 modes of vibration of cantilever beam. Later out of curiosity, I looked up some videos on youtube to see actual cantilever. I found this video which shows the first mode. How do you know that its first mode of vibration? More...

Vibration is energy. "Energy flows, where the attention goes." by Unknown How do your thought change the outcome of reality (vibration)? What media do we express vibration? in sound wave or other format? Does anyone have any suggestions? Thanks in advance for any suggestions...

Someone tells me that every objects has its own vibration, such as stone, water ... When bee is flying, the sound of vibration can be heard at different speed, bbbbbbb ... but not all vibration can be heard by us. Does anyone have any suggestions on what kinds of device can measure...

Homework Statement Scenario 1: Mass suspended from dasphot (damper) and spring Mass=M Damping Coefficient=c Spring Constant=K Scenario 2: Mass supported by dashpot (damper) and spring Mass=M Damping Coefficient=c Spring Constant=K In both cases, derive the equations of motion...

Homework Statement https://www.physicsforums.com/attachment.php?attachmentid=39373&stc=1&d=1317244721 Homework Equations In all honesty I am not sure? The Attempt at a Solution This question was used as a worked example in my first tutorial for Dynamics. The lecturer didn't break it down...

Hi, I've just started a degree in Mechanical Engineering after a HNC and I am having trouble with the Dynamics module! The lecturer literally just blabbed on about Free Vibration and did a worked example of a free vibration system with 1 degree of freedom. He didn't tell us any of the...

I was reading "The physics of superheroes", and it mentioned The Flash being able to increase his kinetic energy to tunnel though walls. I tried to find out how fast he would have to go, assuming he is vibrating (as shown in the actual comic) so will have several tries at trying to tunnel though...

Hi ! I need your help ! I have been kind of stuck with the following problem for a few days : I made measurements on a plate radiating sound with an accelerometer and I found very low values of displacement(1-10 pm !). It seems very very very low (less than 1 atom !) Depending on the...

1. Does the amplitude of a pendulum's vibration have effect on its' frequency? 2. F prop. to L or F prop to 1/Square root L where L is length and F is frequency. 3. Absolute Failure. Cannot Re-Do experiment due to lack of equipment.

Do photons vibrate or oscillate in any way?

I am reading a vibration sensor manuvall that always written in units of "g". what is the meaning of that g. Can some explain me. The document is down here.

I have searched on web but i did not get exact explanation on about these topics. Could someone clear me. I am looking for accelemeter to my pump that can get the information about vibrations.

I have built a 3' by 4' hovercraft (with rounded corners) out of plywood with a pond liner bag skirt. it it powered by either 2 battery operated leaf blowers or 1 plug in electric leaf blower. I have encountered a problem with both power sources. The hovercraft makes a loud vibrating noise...

Hello, I am currently in the process of writing an Extended essay on the the "Effect of Tension on the fundamental Vibration of a circular Membrane" I have already completed the practical side of this by making 5 diaphragms with a 3 micron thick mylar membrane and have written up the methods...

1. The problem statement I have this vibration question, in which i have approach to solve and I came very close to the actual answer but not accuracy correct solution. My work-out solution is 0< k < 28.7 N/m And the correct answer is 0 < k < 27.4 N/m I have tried everythink...

1. The problem statement I have this vibration question, in which i have approach to solve and I came very close to the actual answer but not accuracy correct solution. My work-out solution is 0< k < 28.7 N/m And the correct answer is 0 < k < 27.4 N/m I have tried everythink...

What is “undamped vibration absorption” ? What is “undamped vibration absorption” and how would you use this concept to absorb the vibration of a un-damped, simple mass spring system of mass m and stiffness k oscillating at its resonance frequency?

A violinist places her finger so that the vibrating section of a 1.0g/m string has a length of 30cm, then she draws her bow across it. A listener nearby in a 20 degrees celcius room (speed of sound at this temperature in air is 343 m/s) hears a note with a wavelength of 40 cm. What is the...

Hi All, First time poster on physics forums, but have been looking around for a while now. Very helpful site. I'm currently undertaking a final year Mech Eng project studying the feasibility of installing a pendulum type vibration absorber onto small scale AC induction motors (1-2kw)...

Hi, I am trying to reduce the error in the controller for a stewart platform. At the moment I am trying to experiment with estimating the transfer function of the error, and applying the inverse of the transfer function to the input data. I have an input file sampled at 50hz of...

Hi, I am currently doing an experiment to determine the the viscous damping coefficient (c) of a dashpot. Where you move the position of the damper to determine the effect of the damping but my results show that when the damper is closer to the pivot the damping increases but i thought the...

Just a short question. As part of a dyno project, I am coupling two dc motors together with a timing belt. To allow the same rig to be used for different test motors, I am considering mounting this (test) motor on a table, which can be positioned in two directions on leadscrews. This would...