All Questions
148 questions
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What is the exact nature of molecular vibration in solids and how does it relate to an object's natural fundamental resonant frequency?
This is my understanding and trail of thought on the topic in the title, and I would like to hear from others with a better understanding of the subject if I am on the right track or not.
I will begin ...
- 11
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1
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40
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What really is natural frequency and resonance?
Shouldn’t the frequency of an object depend on how much I push it from one end if the other end is attached?
And what’s resonance? In my textbook there is no such explanation to what is actually is ...
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40
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What are the different types of resonances in forced oscillation systems?
I'm currently studying resonances in systems subjected to forced oscillations and have come across various terms and cases that I'd like to understand more clearly. Specifically, I am analyzing a ...
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33
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What duration of a white noise burst is required for it to be "white" at a given frequency or frequency range?
I am running white noise bursts (with very short ramps on/off to prevent discontinuities) through underdamped resonant bandpasses which are tuned to any given $f_0$ and an underdamped $Q$.
Continuous ...
- 343
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Is natural frequency a local or global property?
Some objects have a natural frequency. This can be anything from a metal ball to a table, etc. When we hit such an object, it will start vibrating with a certain frequency $f$. Because of damping the ...
- 1,502
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Should natural frequency be modeled using molecules?
Consider an object. This can be anything from a metal ball to a table, etc. Now this object has a natural frequency. When we hit the object, it will start vibrating with a certain frequency $f$. ...
- 1,502
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67
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String vibration dimensions
We're all familiar with the typical diagrams of standing waves of a string, as in this image from Wikipedia:
The thing that bothers me is that they ignore the reality that the string is vibrating in ...
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How can one explain the small amplitude resonance before the onset of main resonance condition?
I was using a sonometer to verify the frequency of a.c. supply in the lab is 50 Hz. For this the equation I used is
f=(1/4L) x Sq. root (T/m)
I set tension T = 4.9 N by hanging 0.5kg mass
mass per ...
- 1,395
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91
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Why do you feel ripples by sliding finger on an AC-powered macbook surface?
It doesn't have to be a MacBook exactly, other switched power supply powered metal case devices are good enough, but MacBook is the most common.
It must be AC powered; the effect disappears when ...
- 128
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132
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Non-resonant source in a conducting cavity, what happens?
First of all I'm aware of this post but my question is a little different.
Say we have a perfectly conducting cavity with supported frequencies $\omega_n$ and a harmonically varying source within ...
- 1,810
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Can someone please explain how is the setup stated below apparently causing amplitude resonance in spite of different frequencies?
Suppose I have a pendulum such that its natural frequency is $2 Hz$.
I release it from One extreme by striking it with a tuning fork of frequency $1 Hz$. Now in $0.5s$, the pendulum will undergo 1 ...
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Fourier Transform of Damped Oscillations - Zero Frequency Peak and Shift [duplicate]
A damped oscillator has the time evolution:
$$ y(t) = e^{-\Gamma t}\cos^2(\tilde{\omega}_0 t)$$
where $\Gamma$ is the damping rate, $\tilde{\omega}_0^2=\omega_0^2-\Gamma^2$ and $\omega_0$ is the ...
- 137
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2
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166
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What do we mean by 'resonance frequency' of a system?
Whenever we talk about oscillations, we generally take the term 'resonant frequency' for granted, but I don't understand what this frequency depends on.
For example, if we talk about a freely ...
- 87
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412
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Multiple Pendulums and Resonance
Set up with multiple pendulums suspended from a connecting string. Pendulums 1 and 4 have the same lengths and hence, the same natural frequencies. Others(pendulums 2, 3 and 5) are of varying ...
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Can cyclotron/gyromagnetic resonance occur if the peak of an AC wave corresponds with the resonance frequency?
So basically I'm curious if it's possible for cyclotron resonance to occur with a non-static, AC magnetic field if the frequency of it is equal to the cyclotron resonance frequency at the peak AC ...
- 403
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703
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What is the name for this type of curve?
I encountered this curve in the notes for a physics experiment:
It was described by the equation
$$
A = \frac{kA_0}{m\sqrt{\left(\omega_0^2 - \omega^2\right)^2+(2\gamma\omega)^2}}
$$
EDIT: I think it ...
- 339
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979
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How is maximum amplitude of resonance achieved?
Lets take a simplest case of a narrowly tuned system and the outside force exactly at the natural frequency of it. The first pulse will go through, bounce back somewhat weaker and get reinforced by ...
- 185
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1
answer
2k
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Why damping affect natural frequency of simple harmonic motion? [duplicate]
I am curious about that since damping will not affect frequency of SHM, then why it does affect on the natural frequency of the SHM. In the resonance damping graph the peak amplitude become lower but ...
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1
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203
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Measured frequency of the sound produced when blowing in a bottle is half of calculated
Preparing one lecture about resonance in cylindrical tubes with one closed end, I decided to make some experiments to compare calculated frequencies and measured ones.
We can find anwhere (click here, ...
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Does resonance still occur at half, a quarter, etc. of the resonant frequency?
Examples of resonance that I have seen are pushing a swing and shattering a glass.
I know the swing analogy, that if you push at the right frequency, you can make the swing go higher and higher. My ...
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Fourier Component And Resonance
Wikipedia defined Resonance as the following : Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is ...
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691
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How can you change the resonant frequency of a solid guitar body?
I am trying to figure out if it would be possible to change the resonant natural frequency of a solid-body guitar. For example, let's say it resonates at 100 Hz and I want it to resonate at 200 Hz. Is ...
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253
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Does air column change its frequency to one of its modes as and when needed?
The question might make it sound like I'm considering air column to be a conscious entity kinda thing, but what I really mean is,
Say I've a tuning fork ringing and I bring it near a test tube with ...
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828
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Calculate the Frequency of Clamped Bar
I'm trying to calculate the resonant frequency of a clamped bar or rather I'm trying to calculate what length of bar to use to get a certain frequency. The goal is to be able to use this to make ...
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105
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At resonance, there is infinite oscillation (new)
As per a previous question:
Transient behavour For a driven harmonic oscillator:
I was trying to show an exponential increase in amplitude using the transient solution, however I still got the sake ...
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3k
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Can't understand Resonance in an Air Column
In this image about resonating air column in my book, they say that resonance occurs at those specific lengths marked in the diagram. However,
its also said that natural frequency of air column ...
- 1,250
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212
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What is the reason that the vibrating body gradually acquires the frequency of the external periodic force in forced vibration?
When an external periodic force is applied on a vibrating body the body no longer vibrates with its own natural frequency but it gradually acquires the frequency of the applied periodic force.
I don'...
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280
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How can we find right resonant frequency of a structure?
Structures have infinite DOFs, so it possess infinite mode shapes. How can we find out the right resonant frequency out of the infinite resonant frequencies so that we can save our structure?
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What is the difference between Natural frequency and Resonant frequency? [duplicate]
I was previously under the impression that natural and resonant frequencies are the same. However, after doing some research they don't appear to be the exact same. Could someone please explain the ...
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168
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Can natural frequency be produced by damped vibrations?
In my book it's written that when the tuning fork A is is struck on a rubber pad then it starts vibrating with natural frequency (though not written but if it's not vibrating with natural frequency ...
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247
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How does time period of vibration of a body depends on the shape and size of a body?
My books mentions that time period of vibration of a body depends on the shape and size of a body. But it does not give any reason behind the fact. So I searched on the internet but failed to find any ...
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2k
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What exactly is the natural frequency of an object?
My book defines natural vibrations as:
THE PERIODIC VIBRATIONS OF A BODY IN THE ABSENCE OF ANY EXTERNAL FORCE ON IT, ARE CALLED NATURAL VIBRATIONS.THE TIME PERIOD IS CALLED ITS NATURAL PERIOD AND THE ...
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Why are the resonant frequencies for displacement, velocity and acceleration different in a damped oscillator?
Consider a driven harmonic oscillator under a sinusoidal force $x''(t) + \gamma x'(t)+ \omega_0^2 x(t) = F(t)$. In the regime of light damping ($\omega_0/\gamma > 0.5$), we find resonance (maximum ...
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Finding the resonance frequency for forced damped oscillations
I have a problem regarding a forced, damped harmonic oscillator, where I'm trying to find the resonance frequency. I have calculated the frequency for free oscillations as $$\omega_{free}=\sqrt{\frac{\...
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Phase difference between the driver and the oscillator
Please could someone explain the concept in the text below for me?
In a driven oscillator, the phase of the driver and the phase
of the oscillator are not always the same. At low frequency
($\omega\...
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Does amplitude affect the resonance between two distant objects?
I apologise if this is a stupid question but I haven't studied physics in over 20 years!
I think I'm correct in saying that sound waves have a number of characteristics (including frequency and ...
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871
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What is the resonant frequency of ice? How could you calculate the resonant frequency of ice for a cylinder of ice? [closed]
Can vibrating frequencies break apart the structure of ice? Or could electromagnetic frequencies do the same?
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3
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106
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Why does resonance take place? [closed]
Resonance takes place when external driving frequency equals the natural frequency of an object. I know every objects have their natural frequency.
But I can't see everything vibrating on its own, ...
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Finding natural frequency of animals lung [closed]
I'm currently trying to get my research paper but I still can't wrap my head around how can you measure natural frequency of lungs for example. I've tried searching countless article and journal but ...
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0
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85
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Identifying speech sounds from sound waves [duplicate]
TLDR: How do we differentiate, say, a "A" from a "O", how do we identify speech sounds? If formants are the key, how is it possible to identify it regardless of the pitch (...
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3
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931
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Can an object keep changing its Resonant Frequency?
I was studying Acoustic Resonance and Resonant Frequencies and learned a lot ...
but I have a question which probably the web doesn't seem to answer!
Can an object(any object)keep changing its ...
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What is a linear system?
I was reading about Resonant Frequency, and found a lot of information about it: like its uses in daily lives, for eg: swing, pendulum. etc
I also read about its advantages and disadvantages but the ...
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The resonance frequency of a steel ball
I wanted to find the resonance frequency of a steel ball.
I assume that gradient disappears on the surface of a ball.
I knew that I can find it solving 3D wave equation in spherical coordinates. Due ...
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Forced oscillation resonance frequencies [closed]
Given this forced oscillator:
$$
\ddot{x}+\gamma\dot{x}+\omega_0^2x=\frac{F(t)}{m}
$$
Where $F(t)$ is:
$$
F(t)=\sum_{n=1}^{\infty}\frac{4F_0}{n\pi}\sin\left(\frac{2n\pi t}{T}\right)
\hspace{0.4cm} \...
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How do earthquakes of different strengths affect buildings of different heights?
Why is it that short buildings respond more to high frequency oscillations while tall buildings respond more to low frequency oscillations?
I would assume that how they react is related to the natural ...
- 3,494
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Intuitive understanding of the resonance of a bridge
Dynamics of strides, walking and corresponding force cycles: In the civil engineering literature, it is known that the resonant frequency of a bridge should not be the same as that of the strides of ...
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641
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During sympathetic resonance in a piano, are new frequencies generated?
Sympathetic resonance in a piano is the phenomenon of one string being excited, transmitting its sound to other strings that will then start vibrating if they have common frequencies.
For example C2 ...
- 3,256
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Resonance of a damped harmonic oscillator under forced oscillations [closed]
Suppose we have a damped harmonic oscillator and we also apply an external force such that our system oscillates in steady state. If the frequency of my force matches the natural frequency of my ...
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Measuring the natural frequency of a spring-mass system with the graph
On a graph of a system under a external force y = distance and x = time where the external force start at t = 0, it's easy to find the driving frequency.
$$F = \frac{\omega}{2\pi}, \omega = \frac{2\pi}...
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If frequency is the characteristic of a source and remains constant why does it increase when tension of a string is increased?
So as I've been taught, frequency is a characteristic of the source and it does not change. But, then there are questions where when the tension of a string increased and frequency increases. Can ...
