Oscillation is the repetitive variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. The term vibration is precisely used to describe mechanical oscillation. Familiar examples of oscillation include a swinging pendulum and alternating current.
Oscillations occur not only in mechanical systems but also in dynamic systems in virtually every area of science: for example the beating of the human heart (for circulation), business cycles in economics, predator–prey population cycles in ecology, geothermal geysers in geology, vibration of strings in guitar and other string instruments, periodic firing of nerve cells in the brain, and the periodic swelling of Cepheid variable stars in astronomy.
In descriptions of a VSM, the induced voltage in a coil is shown to be emf = -dPhi/dt = - (dPhi/dz)(dz/dt). From here, everyone seem to jump to a solution of emf = 2*Pi*A*f*m*sin(2*Pi*f*t).
That makes some sense: in this case, you can define z = A*cos(2*Pi*f*t) so (dz/dt) =...
I saw this on the local TV news tonight (I live in Silicon Valley not far from Stanford). It looks to be a very promising and innovative treatment for Parkinson's Disease that is showing some amazing early results (led by Stanford Medicine researcher Peter Tass, MD, PhD). They are calling for...
When the question says 8 antinodes, doesn't that mean N=8? but when I do 2L/8, I get 0.24.
To get the right answer you do 2LN, but that doesn't make sense to me for I thought the equation was 2L/N??
My attempt:
p and T allows us to calculate ##Z=402 \frac{kg}{sm^2}## using ## Z=p*\sqrt(\frac{\gamma*M}{R*T})## . The sound intensity level at 10 meters allows us to calculate the intensity at 10 meters to be I=10``````^{-7} W/m^2 using ##50 = 10*log(I/I_0)##. Then, using the formula...
Here is the question that is is given to me
Part a:
Part b:
I have given this a go and was wondering if my answer seems reasonable.
I had worked out that the mass per unit length (mu) is also the density * cross sectional area of wire
Thanks!
This question reminds me of the interpretation of the "wave packet" in QM for a free particle moving freely in the whole space; but in QM it is obvious that plane waves can't be of physical meaning. Now consider a guitar string (fixed at both ends) and suppose the solution to the wave equation...
Thinking of building a vibrating compactor to compact dirt and gravel for a new driveway section. I already have a horizontal shaft 13 horse honsa engine. I have some scrap steel. My question is concerning the exiter/vibrator. I was thinking of mounting 2 pillow block bearings with a pipe. A...
The fig. 1.1(a) is a mass m attached to a spring that is fixed to a wall. I don't understand what does "a sudden momentum impulse" means. Is it an external force o what?
I imagined that the new equation of motion would be
md^2x/dt^2+dp1/dt-kx=0
md^2x/dt^2+mdv1/dt-kx=0
is this the equation i...
I am curious if the motion of massive object can effect it's gravitational influence due to the fact that gravitational waves travel at the speed of light.
For a weak analogy, consider how a small object can make bigger ripples in the water if it is moving around more. I am curious if there...
1. The problem statement, all variables, and given/known data
So I'm doing an IB extended essay on the relationship between frequency and tension of a violin string. As you apply more tension to the string (using weights and pulley), the frequency will be higher, as shown below. There's not too...
Homework Statement
A second harmonic standing wave has the known quantities of Amplitude (max y at antinode) A, maximum velocity (y=0 at antinode) v, string length L, tension in the string T.
Given that we know that it is second harmonic, we can assume that λ = L
How can one determine the...
Hello All,
I have come across a problem, which has troubled me for some time now. What needs to be done is the following:
A mass on a rod 0.6m (mass less) has a mass of 1 kgr attached at the end of it. The rod needs to be rotated 60 degrees, within t=120 sec (see image). What I would like to...
Hi, I am new here so hopefully this is the right place to ask a question like this. Forgive me if I have trampled a rule. If I have, please let me know what I should do to ask this question.
If you take a wire with a flowing DC current and vibrate it, can it radiate as a radio transmission...
The blue and red lines represent a very stiff string The blue section is plucked and oscillates. The vibration energy is carried through to the red section.
This is what I don't understand.
A) Is the red section a forced oscillation at the resonant frequency of the blue section?
B) Will the...
I am in the process of trying to develop a modal drum synth. I have the following graphics as references for the frequencies of some of the first modes relative to the fundamental:
This is a good start. But I want to be able to model more modes than just that.
What is the formula required...
Homework Statement
Suppose we listen to the sound of a vibrating string with a pickup that is sensitive to the motion at a point 1/3 of the string's length from one end. Which statement is true?
A.) We will be able to hear all of the modes except the third
B.) We will not be able to hear the...
Homework Statement
A violin string is plucked to the shape of a triangle with initial displacement:
y(x,0) = { 0.04x if 0 < x < L/4
(0.04/3)(L-x) if L/4 < x < L
Find the displacement of the string at later times. Plot your result up to the n = 10...
Homework Statement
So I don't really understand what the professor means by "show why the displacements y(x,t) should satisfy this boundary value problem" in problem 1. Doesn't that basically boil down to deriving the wave equation? At least in problem 2 he says what he wants us to show...
I've been trying to come up with wave equations to describe the motion on vibrating rectangular (more specifically, square) membranes. However, most paper I find assume fixed edges.
What are the boundary conditions I need to apply to the 2D wave equations in order to have an free boundary in a...
I know that time dilation effects everything that moves in relation to everything else that's around the thing that moving. Does that also include vibrating and spinning thing and if it does how so?
When the pendulum in Problem 3.8 is vibrating freely in unforced oscillation, the amplitude of its swing decreases by a factor of e after 75 cycles of oscillation. (a) Determine the Q-value of the pendulum. (b) The point of suspension of the pendulum is moved according to ξ = a cos ωt at the...
Homework Statement
From the equation of best fit, determine the wave speed, v, for your string.
Homework Equations
f=(v/2L)n
The Attempt at a Solution
So I am supposed to find the speed of a wave using that graph and data. Do I just take the slope and replace the (f/n) in the equation? I...
Do we know enough of string theory to say that because a quark is more complicated, in the sense that the quark experiences four forces verses three for the electron and two for a neutrino, that in terms of string vibrations quarks will have more complicated vibration patterns than electrons and...
Hi there,
I'm solving the equation for the transverse vibrations of a Euler-Bernoulli beam fixed at both ends and subject to axial loading. It's a similar problem to that described by Rao on page 355 of his book "Vibration of Continuous Systems" (Google books link), except the example he uses...
Homework Statement
the equation of a stationary wave produced on a string whose both ends are fixed is given by
y= [0.6sin(pi/10)x]cos(600pi)t
what could be the smallest length of string?Homework Equations
k=2pi/wavelength
The Attempt at a Solution
i got the wavelength to be 20 but don't know...
Homework Statement
A particle of mass m is on a massless string of length 3a, which is held horizontally across with a tension T(which you can assume doesn't change with the small vibrations). The particle is a distance of a from one of the edges. Set up a diff. equation that describes the...
Skip to the good stuff at 1:41 and 1:52 and anywhere you see paint, can't embed link at the right time.
Note the entire speaker flexing at 1:42 (slow both links down further if you can).
Hey guys, how are you?
I just have an idea but can't figure it out how to solve it. Is it possible to generate electrical energy from a (high power) transformer vibration using piezoelectrics?
Hello,
Just for curiosity...
Is Hooke's law valid for a vibrating massive spring ?
I have done some calculations using both Newton's 2nd Law and the conservation of energy to a horizontal swinging spring connected to a small block in the absence of any friction. I have found that the tension of...
Hi,
I am designing a vibrating platform that will move strictly up and down (total displacement of 1 inch). The load on the platform will vary between 0 and 160kg.
The mechanical assembly/mechanism (which is underneath the platform) is
motor>belt>flywheel>crank attached to a 1 inch shaft long...
I've just recently learned about Yves Clouder's hydrodynamics models that show quantum mechanics behaviour emerging from a vibrating fluid. As a "born-again student", this seems very exciting to me - especially in the sense that at the very least it offers a mental model that helps come to grips...
I have created such vibrating feeder model on SW but on ANSYS I'm only analyzing the frame.
1)How do I set up boundary conditions, I think I need elastic supports?
2)In modal analysis I have elastic, fixed supports, remote displacement - which should I use and in what directions?
3)Do I perform...
Riddle me this.
If it was possible to vibrate at near the speed of light, would that still create the effect of time passing faster for you but your surrounding passing through time at the same rate?
Just wondering. I am aware that A) Time travel backwards would not function, due to the...
Hi
Likely a stupid question.
If atoms vibrate with heat, why don't hot objects make a sound, i.e transferring vibrations to the surround atoms (air) into our eardrums?
They vibrate on ultra-infra sound? Or it's a extremely weak sound? or this is not the same vibration as the cause for sound? or...
So our professor showed us wave patterns on a vibrating plate, by sprinkling powder over it. I'm curious as to why it behaved as it did.The powder moved to nodes, but I'm not sure why. I think it just gets bounced around until it lands on a node, which is stationary, so it then stays there.
Is...
Homework Statement
The wire has mass 250g and is tied down at both ends. It has a length of 12.50m and a fundamental frequency of 25.0 Hz. It has linear mass density.
Sound travels at 344m/s in air. Calculate the frequency of the sound waves produced when the wire vibrates at its fifth...
Hello,
I am an electrical engineering student and I was hoping some body here could help me out with a cantilever question.
I want to model a vibrating cantilever with a mass at the end. I am doing this for a project where I wanted to model a Wurlitzer 200 Electric Piano. The way they produce...
Can I get the voltage generated by a vibrating coil around a magnet as a function of the frequency and amplitude of the vibration (given all necessary informations about the coil and magnet)? What would that function be? Also, what information about the coil and magnet would be sufficient and...
Homework Statement
When displaced from equilibrium by a small amount, the two hydrogen atoms in an H2molecule are acted on by a restoring force Fx=−k1x with k1 = 500N/m.
Calculate the oscillation frequency f of the H2 molecule. Use meff=m/2 as the "effective mass" of the system, where m is the...
Homework Statement
Calculate <K>, the expectation value of the kinetic energy for the ground state of a pair of vibrating nuclei (assume internuclear distance--hence -infinite to +infinite)
Homework Equations
K = -h2/2(mu) d2/dx2
where (mu) = reduced mass; m1m2/(m1+m2)
and
wave(x) = (a/pi)1/4...
Homework Statement
A wire of length 1[m] vibrates with the base frequency which is 200[Hz]. the specific mass is 8[gr/cm3].
The maximal acceleration at the middle is 80,000[cm/sec2]. what is the amplitude
Homework Equations
Newton's second law: F=ma
The cosine sentence: A^2=B^2+C^2-2BC\cdot...
Hi.
Can you do a computer simulation of a membrane with a standing wave(s)/node(s) with a shape of a cube or cone?
It is possible on a string so why not on a membrane.
Can you do a computer simulation of a spherical membrane with a standing wave(s)/node(s) with a shape of a cube or cone...
Hey everyone, I'm currently working on a project to construct the Bessel function of a vibrating surface of water in a cylindrical tank. My basic idea is to have a way of observing a point on the surface of water and obtain distance vs time data to that point (which will rise and fall with wave...
Hi,
Attached is the equation relating the vibration of a sphere radius R, to the pressure field it generates. ρ is the density of the medium in which the sphere sits.
The article I got this from just states the equation - I haven't been able to find anywhere that derives this equation...
I am quite aware of the Physics behind Stationary Waves and how this is responsible for the different notes we hear on a musical instrument; a guitar for instance. What I don't fully understand is the classification of the oscillations of the string. Is it a free oscillation or a forced oscillation?
Homework Statement
Effective potential of atoms in molecule of IBr can be described as ##V(r)=V_0[(\frac{r}{a})^{-8}-10(\frac{r}{a})^{-4}]##, where ##a=1nm## and ##V_0=0.1eV##. Calculate the first three vibration states if the potential close to minimum is harmonic. ##M(I)=127g/mol## and...
So we're studying resonance.
It says that it occurs when an external periodic force acting on a body is exactly equal to the natural frequency of the body. The body then begins to vibrate with greater/increasing amplitude and intensity.
And so what I want to know is that is there a...
Hi all,
Posted this in general as I think my question could span a number of physics fields.
I was doing some work on Turbulent flow this evening and whilst on Wikipedia I got myself reading links after links until I came across a link called "Amplitude Death" and this got me thinking...
Homework Statement
If the phase of vibrating sources was changed so that they were vibrating completely out of phase, what effect would this have on an interference pattern?
Homework Equations
n/a
The Attempt at a Solution
This question undermines my understanding of...
Homework Statement
A string of length l has a zero initial velocity and a displacement y_{0}(x) as shown. (This initial displacement might be caused by stopping the string at the center and plucking half of it). Find the displacement as a function of x and t.
See the following link for...