Frequency is the rate of repetitive aspect in the amplitude over a given dimension.

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Why aren't the lengths of the bars on a toy glockenspiel proportional to the wavelengths?

As you might already know, frequency of musical notes is arranged in a such a way that if, for example, an A note has frequency of $x$, another A note which is placed one octave higher would produce ...
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0answers
12 views

Interpretation of Evanescent Elastic Waves for Material Damage

In elastodynamic theory, when the slowness vector is imaginary, the resulting elastic waves are called evanescent. I have read that this corresponds to exponential decay. I have also read that complex ...
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3answers
46 views

Harmonic frequencies of a guitar string

I'm studying harmonic frequency at the moment but I'm just a bit confused about something. How are more than one different frequencies able to be produced from plucking a guitar string (fundamental ...
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43 views

standing waves on a string [closed]

I've a problem that I can't solve, could someone please help me? The problem says: Two strings of a bass vibrate in a normal oscillation mode with the same period of 8.0 milliseconds. If the ...
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0answers
28 views

Power generated in Piezoelectric material

Good day everyone! I badly needed your help. I'm frustrated in plotting the power vs. frequency in piezoelectric material. Based on the equation: $$P = (I^2)R where $I$ is the current, and $R$ is ...
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24 views

How would I go about calculating the frequency and amplitude of a sound produced by a collision?

How would I go about calculating the sound pressure level, frequency and amplitude of a sound caused by a collision, given the velocities of the two objects colliding, their acceleration, densities, ...
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1answer
412 views

Fundamental frequency of a material and its Young's modulus

I wonder if there is a connection between fundamental frequency and Young's modulus of a material. For example, how to calculate the Young's modulus of a glass bar by knowing its frequency spectrum?
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39 views

Is light spectra different for all living bodies? [closed]

As we know that honey bees can see lots of different colours, is it possible that the light spectra is different for them? My main question is that is light spectra different for all living organisms?...
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41 views

A rocket is receding from the earth at [closed]

A rocket is receding from the Earth at speed of $0.2 c$ where $c$ is velocity of light. It emits signals of frequency $4 \times 10^7 $Hz. The apparent frequency observed by an observer on earth is
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1answer
55 views

Cardboard allows AM/FM waves but NOT light - Why?

I am going through Electromagnetic waves. In footnote, the author was giving illustration on transparency of materials. Was going through some references here as well as in Google. Many people ...
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0answers
43 views

Why LiFi can't penetrate like WiFi? [closed]

My common sense says that Lifi signals can't penetrate through walls (since visible light cannot) but other part of the electromagnetic spectrum can, I mean radio signals which power WiFi. So is ...
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0answers
19 views

Ultrasound in hollow tube

Ultrasound in pulse-echo mode (reflection from air-water interface) is used to measure the level in a tank filled with water. Since the level is several meters, a hollow steel tube is used to ...
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1answer
24 views

Light scattering: Why is the natural frequency in air higher than the light frequencies?

In the Feynman Lectures on Physics Vol. I Ch. 32 (Radiation Damping. Light Scattering) it says: On the other hand, if we take the case of light in the air, we remember that for air the natural ...
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3answers
295 views

Can friction change the resonance frequency of a system?

I am simulating the transient response of a mass-spring-damping system with friction. The excitation is given in the form of a base acceleration. What I am not sure about is: can the friction change ...
7
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4answers
302 views

How do electromagnetic waves carry energy?

Its said that electromagnetic waves carry energy. Is this because these waves are made up of electric and magnetic fields which can cause changes to the stuff that falls with in their range? Is that ...
4
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2answers
98 views

Doppler shift and change in intensity of a sound wave

How are the intensity of a sound wave and the Doppler shift of frequency related togheter? That is, if the source or the observer are in relative motion, how does the intensity change? For a sound ...
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1answer
27 views

Can the intensity of a sound wave in a minimum be greater than intensity in a maximum?

Suppose to have two speakers $A$ and $B$ one in front of the other, producing coherent sound waves with the same frequency $f$ and power $P$. In different positions on the line connecting the speakers ...
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1answer
130 views

What is the effect of liquid density on the pitch of a singing wine glass?

In the singing wine glass experiment what's the effect on the frequency produced if the effect of liquids with different densities was tested? Everything else would be kept constant (same glass, ...
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1answer
22 views

Frequency shift in case of wind and no relative motion between observer and source

I've learned the following things about Doppler effect in the case of sound waves The Doppler effect formula is to be used in the air reference frame (where $v_{sound}=343 m/s$, at room temperature) ...
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2answers
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Why do you only hear the bass when someone nearby is wearing earphones?

When someone nearby is listening to music through earphones or headphones, usually you can only hear the bass (unless it's really loud where you can hear the singer's voice and the other instruments ...
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2answers
31 views

Are resonance and resonant frequency the same?

Resonance is when applied oscillation is in phase with natural oscillation. Then, what is resonant frequency?
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3answers
67 views

Notation to represent frequency and acceleration in preparation for algorithms

I hope this is the right place to ask. IMO it's the most appropriate SE site. I would have chosen mathematics; I didnt because I am using units such as force and Hz, and want equations to have ...
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1answer
57 views

Determination of nature frequency and differential equation of vibration of Hartnell governor?

I found this solution for the nature frequency but here it does not include the Ball weight and centrifugal force in the moment balance equation about the pivot (O), it is wrong answer...is not it? ...
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35 views

Beats: frequency of resulting wave vs. beat frequency

The beats frequency heard from the interference of two sound waves with frequencies $f_1$ and $f_2$ is $$\nu=|f_1-f_2|$$ Nevertheless the frequency of the resulting wave is not $\nu$ but the mean ...
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29 views

Conditions to find standing waves harmonics

I came up with a doubt on standing waves conditions. The type of question I find difficult to answer is of the following type. Consider a rope. I do not know if the rope is fixed at both end or at ...
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1answer
234 views

Why does amplitude of a mechanical wave increase and then decrease with increasing driving frequency?

I was doing an experiment where I explore how the frequency of the oscillation of a vibrating water hose (the end of the water hose), affects the amplitude created by the water path (a wave-like ...
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32 views

Is measuring the speed of light using energy and wavelength cyclical?

I would like to measure the speed of light by directly measuring the frequency and wavelength of a light source. In order to determine the wavelength, I wanted to use a diffraction grating and the ...
0
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1answer
35 views

Bohr frequency of an expectation value?

Consider a two-state system with a Hamiltonian defined as \begin{bmatrix} E_1 &0 \\ 0 & E_2 \end{bmatrix} Another observable, $A$, is given (in the same basis) by \begin{bmatrix} 0 &a \...
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1answer
25 views

Pound-Drever-Hall frequency stabilisation technique

I am having some difficulty understanding the Pound-Drever-Hall frequency stabilisation technique, when locking a laser to a stable cavity. As far as I understand: We emit the laser frequency, f0....
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3answers
66 views

Multiples of frequencies in Fourier transforms [closed]

Given a sinusoidal signal with a frequency $\omega$, the Fourier transform ought to simply be a delta function at $\omega$. However, what happens to multiples of these? MATLAB's FFT shows nothing at $\...
0
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2answers
48 views

Why monochromatic waves exist even theoretically

I was reading this question. Where the author made a statement that If I take a wave with period T, it is also true that it has a period 2T, 3T and so on. That is, it has frequencies of 2π/T, but ...
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2answers
64 views

Percent variation of a physical quantity: how to choose who is in the denominator?

I came up with a very basic doubt on percent variation of a physical quantity,say $f$, defined as $$\delta f_{\%}=|{\frac{\Delta f}{f}}|\cdot 100$$ The problem is with the denominator. I'll make a ...
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75 views

The criteria of light

My question is regarding if the "speed of light" 299,792,458 m/s should only apply to certain frequencies of light/colors/amplitude and most the medium in which it travels at 299,792,458 m/s . Shouldn'...
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1answer
259 views

Is it possible to determine maximum frequency of a disc using a relative circumference?

On Wikipedia there is an article that shows how to calculate the relativistic effects on a rigid spinning disc, I am referencing the formula under the "Ehrenfest's argument" section in the link. The ...
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1answer
45 views

Is there a connection between the frequency of a photon and the oscillation frequency of the atom which absorbs it?

If a photon has energy $E$, we know it has angular frequency $\frac{E}{\hbar}$. If an atom has an energy gap $E$ between its ground and first excited state, we know that if the atom is in a ...
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15 views

does changing air velocity change the frequency of sound coming out of a whistle?

If I use an air compressor and vary the velocity of the air coming out, does the frequency of the whistle change too?
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2answers
439 views

Resonate frequency of an object?

Below is a paragraph taken from the web site, physicsclassroom.com: It is often useful to think of these electrons as being attached to the atoms by springs. The electrons and their attached ...
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1answer
173 views

Refractive index and color

Does the color of an object have anything to do with its refractive index, and if so, what is the relation? I tried googling this and searching through the questions on stack exchange, but I haven't ...
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1answer
40 views

Can a flow of current be produced in a wire if its is bombarded with Electromagnetic waves?

If you have a conducting wire and you bombarded it with EM waves, is there a frequency (lower then the threshold frequency to liberate the electrons) that would induce a current within the wire. I ...
2
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1answer
95 views

Frequency of an open air column

Given only the length of an organ pipe to be $2.14 m$, is it possible to find what frequency it vibrates at? If I use the equation $f=\frac{v}{\lambda}$, does the $v$ apply to the speed of sound in ...
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2answers
50 views

Are two waves coherent iff they have the same frequency?

The essential property that two waves must own in order to interfere with each other is to be coherent. Two waves are coherent if their phase difference $\phi_2-\phi_1$ does not change in time ...
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1answer
60 views

what is temperature coefficient of resonant frequency?

I am trying to find the definition for temperature coefficient of resonant frequency, (TCF), but it seems like there is well-defined information about this term. Even for articles in google scholar....
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20 views

How to convert from overtone to harmonics and vice versa?

I was given this question: If the pipe length in a tube is 1.9 m, at the air temperature inside the tube is 28 °C, determine the fundamental frequency of the note played, fourth harmonic and the ...
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0answers
37 views

Can I measure the mode shape frequency of a metal frame with a sound meter

If I 'ping' a metal frame it will resonate in many different mode shapes with different frequencies. I can see those shapes by doing a modal FEA analysis. When I use a sound meter to measure the ...
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4answers
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Is speed of sound really constant?

Does not speed of sound actually depend on the frequency and/or amplitude of the waves? If so, why it is constant?
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50 views

What is the max frequency of sound in a given medium?

When talking about acoustic waves, medium continuity (pressure, density) is implicit. But can the wavelength of an acoustic wave be as small as intermolecular separation? For example, can ~10 THz ...
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3answers
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Is there any truth to interpreting definition of a second as corresponding to oscillations?

As far as I understand the definition of a second, the Cs-133 atom has two hyperfine ground states (which I don't really understand what they are but it's not really important), with a specific energy ...
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What does a sound of infinite Hz sound like?

Say an airplane flies at Mach 1. The doppler effect causes the front of the sound emitted by the plane to reach infinite frequency: $f = \left ( \frac {343+0}{343-343} \right ) f_0 = ∞$ If the ...
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1answer
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Spring system - 3 DoF system and its properties while changing stiffness

I was given the attached 3 degree of freedom spring system with the purpose of analyzing it. I came up with the following equation of motion and then I ran Matlab to calculate the corresponding ...
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3answers
575 views

Spring pendulum - why is it possible to use this equation?

It is known that, when we describe the spring pendulum, we are bound to use the formula $T = 2\pi \sqrt{m/k}$, however, we can go further and set $\omega = \frac{2\pi}{T}$ I ponder why is this ...