Damping Definition and 284 Threads

Hi there, Sorry typo in the title and I can't figure out how to change it! I am just wondering if anyone can help me - does damping (drag) increase the period of a pendulum? As opposed to if it was in a vacuum? I have been trying to figure this out for some time - I know that drag is dependent...

So I am trying to calculate the damping coefficient of air passing around a piston that is oscillating in a tube. The idea is completely theoretical. I don't have any real data. As far as i understand: 1. The viscous sheer stress = mu.du/dy 2. Therefore the viscous sheer force = (piston...

A mass weighing 32 pounds stretches a spring 6 inches. The spring constant is equal to 64 lb/ft.The mass moves through a medium offering a damping force that is numerically equal to \beta times the instantaneous velocity. Determine the values of \beta>0 for which the spring/mass system will...

This is not homework, I need someone to verify (9) and (10) below whether I am correct because I don't have the answer. I need to find the solution of the following: [SIZE="5"]Question Find the solution of the equation for damping vibration string stretched from x=0 to x=L where...

Hi, my question is about determining the damping ratio for the upper spring-damper part of the system given in the link. Is it still r2/(2*sqrt(k2*m2)) or something equivalent should be determined? http://img217.imageshack.us/img217/3148/sprdampmass.png Thank you!

Homework Statement I am working with a problem of damped harmonic motion. I am given that the motion is in a medium that exerts a force of 2N when the speed is 4 cm/s. The mass is 5kg. Homework Equations C = F/v The Attempt at a Solution I thought that the viscous damping...

Evening All, I am looking at a problem where there is essentially a hydraulic cylinder containing a double acting type rod (with an annulus). There will be some holes in the annulus, which will allow fluid to pass through once there is a load on the end of the rod causing it to extend. The...

The problem is: Two damped harmonic oscillator are coupled. Both oscillators has same natural frequency \omega_0 and damping constant \beta. 1st oscillator is damped by 2nd oscillator. Damping force is proportional to velocity of 2nd oscillator. And, vice versa, 2nd oscillator is...

I am given the following information: A 2.20 kg mass oscillates on a spring of force constant 250.0 N/m with a period of 0.615 s, and I am asked to find the damping constant. Can someone tell me what equation to use?

Homework Statement A mass spring system has the following parameters: damping constant is 1.00 Ns/m spring constant is 1.00N/m and mass is 1.00 kg The mass is displaced from equilibrium and released. Through what minimum number of oscillations must the mass move in order to reduce the...

Hi I am new to this community, so don't beat me up too hard :). I have a question about the Hamiltonian when it will simulate the principal system as a harmonic oscillator interacting with the environment which is also an harmonic oscillator (page 291 in "Quantum computation and Quantum...

Homework Statement I'm a little ashamed to post this, because I bet I'm missing something obvious, so try not to laugh... A freely rolling freight car weighing 10^4 kg arrives at the end of it's track with a speed of 2 m/s. At the end of he track is a snubber consisting of a firmly anchored...

I have already built most of the chopper but am trying to add an accelerometer. Let's say the blade is rotating at 600rpm, this is causing vibrations throughout the vehicle at 10hz. I want to make a compartment which doesn't feel most of these vibrations. I'm thinking of building something using...

When a forced oscillation is damped, it is true that the frequency at which resonance occurs decreases right? so does this mean that the natural frequency has decreased too or does it only mean that resonance does not occur at natural frequency when being damped?

Let's say I have a system with multiple oscillatory modes. Is it possible to have anything in this system that resembles critical damping?

I'm using a 3rd party physics engine to run rigid body physics. It just updates the bodies once every 16 ms or so. I'm trying to write an algorithm to predict where free-falling bodies will be in 2 seconds using standard physics equations. I'm having trouble with predicting angular velocity and...

Homework Statement I want to find the damping coefficient of a spring of free length 36.3mm, with load mass of 0.036kg. Homework Equations i need the amplitude of this system, i have the angular frequency, but not the damping ratio. So i was trying to use the formula: damping...

Hi guys, working a project where I need to guess the damping ratio (used for a numerical analysis) based on other properties of a material. We're looking to use an RTV as a vibration damper (we don't need a lot) but I can't seem to get any vibrational properties (called Honeywell, Dupond...

i want to ask ...how can i model sloshing of fuel in satellite feul tank , to an energy sink model... can anybody help me?

Hello MechEs (or anybody else who'd care to reply) I'm about to get a small, but fairly sensitive analytical scale recently (down to 0.01 mg) and now I'm trying to figure out a way to dampen ambient vibration from the room and its surroundings (people walking around, HVAC, etc.) I've got a...

In the design of a loudspeaker, one intuitively seeks a critically damped alignment. We must consider the electrical resistance of the coil, magnetic field strength, mechanical resistance, mechanical compliance, and mass (diaphragm + acoustic load) of the system. The electrical resistance...

im supposed to write a little discussion on mechanical damping practical use...can anyone give me a proper website or note in the internet.....

Homework Statement A 50.0g hard-boiled egg moves on the end of a spring with force constant k = 25.0 N/m. It is released with an amplitude 0.300m. A damping force Fx = -bv acts on the egg. After it oscillates for 5.00s, the amplitude of the motion has decreased to 0.100m. Calculate the...

Lets say i have a magnetic pendulm, (basically a barmagnet suspended from a with a string tabletop) and a conductor at the bottom. The conductor will ofcourse have Foucault currents generated in it, and this due to conservation of energy, will slow down the swinging of the pendulum, reducing...

I have a reciprocating pump running 350 RPM, 2.25" stroke. Piston is double acting (ie: force in both directions). Load is ~30,000 pounds. There's a very small clearance in the coupling between piston and drive train, and this coupling goes through the same motions as the piston (it is...

im trying to model a mass hitting a block of honeycomb aluminum with a DE. is the whole mx"+bx'+kx=F(t) eqn. void because b isn't viscous? Is there a way to get around that?

Homework Statement A small earthquake starts a lamppost vibrating back and forth. The amplitude of the vibration of the top of the lamppost is 6.5 cm at the moment the quake stops, and 8.0s later it is 1.8 cm. What was the time constant for the damping of oscillation? What's the...

Hi, I am working on a problem with a free hanging mass attached to a spring and damper in parallel. I believe my system equation is as follows: my'' = mg - by' - ky My questions: 1) It has been a while since I've taken this course and just wanted to confirm I wrote my system...

Which one of the following statements about an oscillating mechanical system at resonance, when it oscillates with a constant amplitude, is not correct? A The amplitude of oscillations depends on the amount of damping. B The frequency of the applied force is the same as the natural frequency...

If I have mass-spring system with certain damping factor, what is the expected reduction in the damping if the mass is reduced by 25% and the spring stiffness by 50%? It is clear that the damping will decrease but how much? can anyone helps me in that?

Homework Statement A block of mass m rests on a horizontal table and is attached to a spring of force constant k. The coefficient of friction between the block and the table is mu. For this problem we will assume that the coefficients of kinetic and static friction are equal. Let the...

Hi All, I need some basic info of He closed cycle cryos..(like working principle, etc).. I have a compressor, which compress He gas and passed into a cryo's coldhead. So He gas expands in side the coldhead and cools the coldhead..then it again passes into compressor..so the cycle repeats.. I...

I've been somewhat curious about this for a little while: Is there a way to obstruct a magnetic field so that it is weaker in one area and stronger than another. I have attached a picture of what I'm kind of looking for, but also anything that could cause the same effect in terms of...

Qn4. A damped harmonic oscillator involves a block of mass 2.0kg and a spring with a stiffness 10 N/m. The damping force is proportioanla to the velocity of the oscillator. Initially it osicillates with an amplitude of 25cm. Due to the damping, the amplitude fallsto three-fourth of this...

Qn3 A pendulum length of 1m has a bob which has a mass of 50g. It is released from an initial angle of 15degrees. After 1000s, its amplitude is reduced by the damping force of the air to 5.5degrees. What is the value of the damping constant of the air? Ans. I need to check whether what i...

Critical Damping: T/4? I read a few Textbooks on SHM. It happens to be the ones that show no mathematical derivations, that claim that Critical Damping has the period (i.e. time from 0 to equilibrium) of T/4 So I went back to my derivations of SHM considering second order differential...

Critical damping provides the quickest approach to zero amplitude for a damped oscillator. With less damping (underdamping) it approaches zero displacement faster, but oscillates around it. With more damping (overdamping), the approach to zero is slower. I got this from hyperphysics but I...

I am doing an experiment on the pendulum, and i wanted to do something on the damping, i understand a little as i have done some reading on it, the picture attached show the working i have done, i have reached a second order DE and i know little about this. So my question is, can you plot a...

Hi all, I've finished a hypothetical problem in which I have determined the optimum damping ratio $\zeta$ for a specific system. This $\zeta$ value (0.265 in my case) minimizes the peak force transmitted through an object. My next step is to take this $\zeta$ value and find some sort of...

How do you keep the metal object from sticking to the magnet when building a magnetic damping device? :smile:

Hi All This is my first post and I was hoping that someone could help. I have the following attached question regarding a linear damping model (in this case a seismograph). (1) Draw a force diagram. If W=weight, R= air resistance, and H= spring force, then I get W pointing down and both...

Hello. I'm designing a simple prototype home kit for visualising the effects of vibration on various systems. In this case i have a simple spring mass system in compression that will have responses measured by varying initial displacements. As it stands the system will be unforced, and...

Homework Statement A hard-boiled egg of mass 51.0kg moves on the end of a spring with force constant 25.7N/m. Its initial displacement is 0.293m. A damping force f (x) = -bv (x) acts on the egg, and the amplitude of the motion decreases to 0.101m in a time of 4.55s. Calculate the...

I now I have several threads but I need help with them all and thanks to who ever gives their time. Homework Statement A damped harmonic oscillator consists of a block (m=2.00kg), a spring (k=10.0N/m), and a damping force (F=-bv). Initially, it oscillates with and amplitude of 25.0cm; because...

[SOLVED] Pendulum Damping Force Homework Statement I am attempting to find the damping force of my pendulum using Stokes' Law. However, I am having trouble finding the velocity of the spherical object to get this damping force. The radius of the sphere is 0.014m, the viscosity of air is 1.82...

Homework Statement This problem is part of my project for Controls 3B. The project revolves around modeling a bouncing ball that is dropped from a certain height and bounces of the ground. I have been told to use the mass-spring-damper model to simulate the ball while it is in contact with...

Homework Statement The Archimedian principle stetes that the bouyancy force equals the weight of the water displaced by the body (partly or totally submerged). A cylindrical buoy of diameter 60cm is floating in water tiwh its axis vertical. When dupressed downward in the water and released...

Homework Statement A 95.0 cm pendulum is released from a small angle. After 115 oscillations, the amplitude is one half of its original value. The damping is proportional to the speed of the pendulum bob. Find the value of the damping coefficient. Homework Equations b=sqrt k*m A=...

hi, this is a question in my textbook that i don't get: Does a stiff spring undergo slower or faster damping than a less stiff spring of the same legth? i think the stiff one would undergo a faster damping because it tends not to move even though there's a mass attached to it, doesn't it...

If anyone could help with the following, it would be great. I am currently carrying out an experiment for a school project to see how damping affects and reduces the amplitude of the oscillation of a pendulum. For the pendulum I am using a suspended metre ruler and I will count the number of...