Questions tagged [vibrations]
The vibrations tag has no usage guidance.
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Vibrations in Stones and Crystals
I have read studies done that indicate certain sounds can either disrupt or reinforce the molecular structure (I think this is the terminology used) of living organisms. This is based on the idea that ...
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Difference in Sound and Heat
What makes sound and heat distinct ?
The answer is said to lie in the fact that the former consists of vibration in an ordered fashion while the latter is not.
But why would ordered vibration not be ...
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What's the force when there is only mass? [on hold]
There is string of length $L$ ,
clamped at $x=0$ , and connected to spring-mass-damper system at $x=L$ .
The force which spring-mass-damper system applies to ground
is called bridge force.
(This ...
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Can mass be ejected from a black hole within the Schwarzschild radius?
This goes far beyond my limited knowledge regarding the physics of black holes, but my colleague told me this today:
I doubt that if I stand on the surface of a black hole - inside the
...
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Can dispersion relations be derived using Euler-Lagrange equations?
The question is long because of the demonstrations I give, but the problem is simple, so bear with me for a minute.
I am trying to derive the dispersion relation of a semi-infinite system using Euler-...
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Transverse vibration of triatomic molecule from Landau Mechanics Sec. 24
Transverse vibration of a triatomic molecule ABA which consists of two identical atom A and one another atom B such as $\mathrm{CO}_2$ is depicted in page 24 Sec. 24 Landau Mechanics.
The ...
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What are “vibrations” in a field in Quantum Field Theory (QFT)?
For example, in a 2013 article for NOVA Don Lincoln writes:
Everywhere in the universe there is a field called the electron field. A physical electron isn’t the field, but rather a localized ...
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Vibration on me [closed]
My neighbor has a infrared vision google security system. How can They place isolated vibrations on me whenever I walk which they can turn on and off or speed it up. My husband cannot feel it.
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I don't know how to think about this question. Can someone help me? [closed]
I have been having problem with a question from IB past paper. I can't imagine of how this system is working (especially the relation between the spring and the sine wave). Can someone explain what is ...
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Does putting a part under stress change its natural frequency?
It is easy to imagine how tension changes the natural frequency of a wire. Intuitively it happens with a guitar string when you bend the neck.
However, does putting a beam under stress (internal or ...
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Will a cantilever tube vibrate if fluid enters from its free end and flows into the fixed end?
For dynamics of a cantilever pipe with fluid flowing from fixed end towards free end, there are values of frequency for a threshold of flow velocity that gives unstable, stable and neutral systems, ...
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How to measure the mechanical vibration when a hammer hits a nail? [closed]
I want to know the exact location of the vibration sensor that can be placed to measure the vibrations created by a hammer hits the nail.
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Normal mode decomposition of a triangular hexagonal lattice
I was trying to understand and redo the methods used in a previous question:
Vibrational anharmonic coupling and noise-induced spontaneous symmetry breaking in a hexagonal finite mechanical lattice
...
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Physics of a catenary with sinusoidal motion at one end
If we have a catenary line with a mass per unit length of m with one end fixed and the other end moving in sinusoidal motion like $A.sin(\omega.t)$, how would I ...
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Which waves are produced during tuning fork vibration? [duplicate]
In my book, it is written that transverse waves are produced during physical motion of tuning fork. But vibration of tuning fork produces sound which are compressional in nature .
Please tell me ...
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vibration and movement of electric appliance
So, what I am thinking about here is a cooking mixer placed into a bowl which is turned on and left moving on its own. The bowl is such that it does not topple nor the mixer falls out of it.
Once the ...
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Book for electromagnetic waves and radiation
MIT course 8.03SC recommends Electromagnetic Vibrations Waves and Radiation (The MIT Press) by Bekefi and Barrett for extra reading however I am unable to find any soft copy online and its too costly ...
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Why are higher frequencies amplified less by filling a bottle with warmer water instead of colder water?
Out of curiosity I was trying to figure out what makes the sound of hot water versus cold water filling a bottle different, but I'm unable to find any explanation as to why such differences occur.
...
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The Strings have a finite size they can vibrate?
as I searched about the Strings theory I found out this explanation:
Since the strings have a finite size they can vibrate. All the known particles of nature are just different modes of vibration of ...
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What makes quartz oscillators vibrate?
I understand that the principle behind it is piezoelectricity and electrostriction (inverse piezoelectricity), but how does one make the crystal vibrate?
The only thing I can think of is using an ...
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What is the reason behind resonance?
At the technical highschool that I attend, the instructor said that the cause of resonance is that energies increase differently.
Kinetic energy increases quadratically and potential linearly, so the ...
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1answer
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Heat capacity due to Phonon Vibrations
Why does the speed of sound come, in the expression of Heat capacity, from phonon vibrations?
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Faraday waves and Chladni plates
I am a High school student who's writing a research paper about Faraday waves and Chladni plates. I've been doing a lot of research on Faraday waves specifically, as there aren't many sources that can ...
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Optical and acoustic branch
Does a diatomic crystal posses both optical and acoustic branch simultaneously; Or, whether the vibration is either optical or acoustic?
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Why standing wave conditions don't include a phase difference of π
So in order to set up a standing wave on string I can set a travelling wave on it first then let this travelling wave get reflected from a fixed end and this reflected wave interferes with the ...
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What will happen to these colliding strings?
What happens when these two strings collide? Do they cancel each other out, pass through each other or interact in some way?
Thanks.
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sounds of polygonal ring chimes of metal
Suppose we have a number of rings, each of them is constructed from some mass of wrought iron or steel: each ring is a polygon, which I would like to suppose is constructed without welding (so they ...
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Error in FFT (Sectrum) analyzer Instrument
Recently I performed an experiment on finding the natural frequency of vertical cantilever. I used accelerometer and FFT analyzer instrument for measuring it. First I kept the accelerometer near the ...
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Are sinusoidal travelling waves also normal modes of vibration?
According to definition of normal modes, which says if all the different independent parts of a system vibrate at same frequency and their amplitude preserve a fixed ratio then such a motion is a ...
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Shouldn't reflection at the boundary interfere with the original wave to not give any wave?
So I have been taking a wave course, and one thing that I don't understand is how does reflection even allows normal modes of vibration. I'll try to explain my confusion:
Suppose we have a string ...
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Prove from first principles that a guitar string will vibrate at a constant frequency
From experience I am aware that a taught string will generally vibrate with a constant frequency. I wanted to prove this by considering the relation of distance from the resting position, and its ...
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Calculating the power of a pneumatic piston vibrator
I am using a pneumatically-driven piston vibrator to compact a tank filled with granular material. The intensity of the vibrator can be regulated by changing the pressure of the pressurized air fed ...
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1answer
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Using two simple pendulums to estimate $g$
I know that using the period expression for a simple pendulum we can have an estimation of the acceleration of gravity $g$. I encountered the following question
One way of measuring the terrestrial ...
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Vibrating string as a dynamic system
It's known first order dynamical systems had one energy storage (example C, in RC circuits) these systems act as a filter but don't resonate, on the other hand a second order system had two energy-...
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If all harmonics are generated by plucking, how does a guitar string produce a pure frequency sound?
A guitar is a plucked instrument and it is played by plucking a string at an off-centre point fixed at two ends. In general, Fourier analysis tells that all harmonics (the resonant frequencies of the ...
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Why does a metal block make a shrill sound but not a wooden block upon hammering?
When hammered, a metal block makes a shrill sound but not a wooden block of identical shape. Is it that the wooden block vibrates with lesser frequency than the metal block? If so, why is that? Also ...
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Vibrational Question [closed]
A friend recently asked me this question, which I am not even sure how to comprehend...
Three masses are arranged at the vertices of an equilateral triangle and are connected by springs along the ...
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2answers
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Human perception of temperature
I had the following thought experiment recently: Suppose we have a vibrating plate for which we can tune the amplitude and frequency of vibration, and imagine we hold a finger against the plate. For ...
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Why is the UV absorption band for molecules not a sudden transition?
From what I have read, when a molecule in solution or gas is excited, it does so from ground state, but may gain the energy for vibrational transitions as well. This would lead me to expect that there ...
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Can the vibrations from the Earth affect gravitational wave detectors?
I was very interested in gravitational wave detectors and how they work exactly. From what I know they set up two lasers with mirrors set up to cancel each other out. Then if movement is detected from ...
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Laser creating weird patterns on screen when reflected from a vibrating membrane
Me and a few friends were doing an experiment today in which we took a membrane stretched over a speaker, and a small mirror in the center of the membrane. We reflected a laser off the mirror on a ...
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Frequency modes of the rectangular shell
The shapes of three natural modes having the frequencies $w_1$, $w_2$, $w_3$ of the rectangular shell are presented in the figure. The exciting pressure $p(t)$ applied uniformly all over the one side ...
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Degrees of freedom of gas molecules
What is the degrees of freedom of a three dimensional polyatomic molecule when only one vibrational mode is excited?
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How does a guitar work?
Here are four different possible ways:
The plucked string vibrates longitudinally, vibrating the air around it. This vibrating air then causes the air inside the sound box to vibrate also, which ...
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1answer
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What is quantum molecular movement? [closed]
Q: What is quantum molecular movement? And what are some examples of quantum molecular movement?
I’ve been studying a wide arrange of things but one of the top things I don’t understand is quantum ...
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Why do objects have a Natural Frequency? [closed]
Why should an object even have a natural frequency, why not vibrate at any other frequency? This just sounds nonsensical.
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Are acoustic phonons always the lowest energy vibrational modes in solids?
In solids with unit cells containing more than one atom, the normal modes show acoustic and optical branches. The number of optical branches is proportional to the number of atoms in the unit cell, ...
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What is the equation for a convex catenoid, and is it subject to an oscillation on minimum surface?
I want to re-think the shape of a vibrating string to find a source for frequencies that are not emitted by the fundamental mode but do not require points that are fixed and moving at the same time, ...
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Change in vibrionic energy in at atom at a higher excited electron state
I was studying the coupling of Vibrational and Electronic energies and was left confused at one aspect of the subject.
Consider the image showing a transition from one electronic state to a higher ...
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Coupled pendulums at half height
Suppose we have the system described below (poor quality but it'll do the trick). We have two pendulums of mass $m$ coupled by a string of constant $k$ placed at a height $a$ from the top (as shown). ...
