Questions tagged [frequency]
Frequency is the rate of repetitive aspect in the amplitude over a given dimension.
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Dispersive wave and wavelenght
Supposing that we have a dispersive medium, for which it is established that
$$\frac{\omega}{k\sqrt{1+a^2k^2}}=v.$$
That tells us that if $a>1$ then as the frequency of the wave gets higher and ...
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Basics of photoelectric effect
DISCLAIMER: I have not yet fully entered into the vast field of quantum mechanics and and was reading about the photoelectric effect as a part of chemistry, however I feel, the topic of structure of ...
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An RLC series circuit with current equal to one half the resonant current [closed]
Consider a RLC circuit coupled in series supplied by the AC voltage v= 30 sin(w t),
R=50 W, L= 600 mH, frequency f=5 kH. The inductor is a solenoid and the capacitor has cylindric configuration. The ...
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How to convert volt-second data into power-frequency domain?
guys, I am new to physics. Due to my project, I have to utilize my data in the frequency domain. However, my data is in the time domain. So I wanted to ask how I can transform my Volt-time domain data ...
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Is possible to "isolate" some audio frequency? [closed]
I want to know if is possible to "isolate" some audio frequency for certain human that only this human can hear this "frequency spectrum", some animals can hear certain frequencies ...
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Why is this a negative frequency?
In general, i have noticed that i have simple accepted the fact that $$\psi = e^{i(kx-wt)}$$ represents a positive frequency, and $$\psi = e^{i(kx+wt)}$$ represents a negative frequency.
After a time ...
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Are photons with different frequency distinguishable?
When i learn statistical mechanic, the teacher told me that photons with different frequency are distinguishable, i confused.
And the teacher say also photons with different polarization, direction ...
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Can Low-Freq sound wave with High-Amplitude destroys human ear?
Humans can detect sounds in a frequency range from about 20 Hz to 20 kHz. So that's mean human unable to hear 1 Hz frequency sounds since it's far under 20 Hz.
At detectable frequency of human like ...
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Frequency Integration of Green's Function
If one has a Green's Function that has been projected into the Helcity basis (from spin) of the from
\begin{equation}
G(\mathbf{k},\omega)=\sum_s\frac{1}{\omega-\epsilon_{\mathbf{k},s}+\mu+isgn(\omega)...
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Could a Haptic Actuator change the natural frequency of an object?
Could a Haptic Actuator which can operate in the 10 - 500hz frequency range be used to modify a wooden objects natural frequency?
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How to change frequency of a millimeter wave?
I want to know, is there a surface or medium that can change or shift the frequency of a millimeter-wave?
I have seen some metamaterial elements that do it for THz and some optical methods, but I ...
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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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Is there any end to the electromagnetic spectrum? [duplicate]
Is there any theoretical end to the electromagnetic spectrum…
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What happens to the time period when refraction occurs? [duplicate]
I was studying light and had a doubt that when refraction occurs (rarer to denser just assuming) then frequency remains same but lambda (wavelength) and velocity decrease. But I cant quite figure out ...
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Natural frequency of electrons and the Hydrogen atom
Natural frequency is the frequency of a system when it vibrates freely without damping. I am in need of clarification about the definition of natural frequency at the atomic and molecular levels.
Let'...
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How to calculate the overall harmonics of a system of tubes?
Let's say there is a tube closed at one and and open from the other. The open end is connected to another tube (of smaller diameter) which is open from both ends. How can I calculate the overall ...
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Are gamma rays the limit of the frequency photons can attain, and if yes, why? [duplicate]
Recalling that the Planck constant is $6.62607015 \times 10^{-34} m^2kg/s$ and taking into account the formula $E=hf$, for the energy of photons, we can rapidly derive the energy of gamma rays, which ...
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Create a plausible vibration signal from a sliding RMS window
So lets say I have observed many vibration signals and build a sliding window of the RMS of said vibration signals as well as other statistical measurements such as the variance and nth order ...
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What frequency of cord shaking maintains the same vertical motion for a point on the cord after increasing the wave speed on the cord?
I'm studying for my upcoming AP Physics 1 exam but can't figure out this problem
A student shakes a horizontally-stretched cord, creating waves. The graph above shows the vertical position $y$ as a ...
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From discrete to continuous superposition of waves, what happens to omega?
The Wikipedia page on group velocity uses the superposition of two cosines (of slightly different wavenumbers and angular frequencies) to show that group velocity $v_g = \frac{d\omega}{dk}.$
The sum ...
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Frequency and length
Why is pitch inversely proportional to length of an instrument?
I think i know meaning of frequency but if anyone can also explain frequency according to higher level physics it shall be great.
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Why can we hear instruments but not voices?
I've seen this graph:
But I don't get something. Consider the 2kHz line (highlighted in red).
This graph implies we can hear an orchestral instrument at 2kHz before we can hear a human at the same ...
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Why is the refractive index of blue light larger than red light in water while the refractive index of radiowaves is larger than both?
So I thought the reason why radio waves have a relatively high refractive index in water is because they have a low frequency which increases the permittivity, but blue light that has a higher ...
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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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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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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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Speed of the Standing Wave in A Pipe
I’m studying standing waves and I got stuck with this question. The answer key says ‘A’ is the correct answer, but I think ‘B’ is the correct answer.
My reasoning. The speed of the wave depends on the ...
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Does, and if so, why does the frequency of light and wavelength of light affect the photoelectric current?
It makes sense that intensity of light affects the photoelectric current, but what about the frequency and wavelength, given that intensity remains constant?
The formula for intensity would be I = nhf/...
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Is frequency inversely proportional to wavelength Squared?
In our QM intro class our professor was introducing us to concepts of energy, momentum, frequency, wavelength etc of photons an electrons, On one side of the board he had the various expressions for ...
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Relation of frequency of light and photocurrent in Photo-electric effect
As we know that the frequency of incident light is postulated to have no effect on the photocurrent. But coming to think about both quantities should be related. Consider the formula-
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Why doesn't angular frequency change in damped simple harmonic motion?
I recently carried out an experiment varying different factors affecting simple harmonic motion, namely friction and air resistance. Whilst carrying out research for this, I found the relationship ...
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Physical interpretation of FFT frequencies
I need to calculate the PSD of a discrete signal and want to compare it to other processes. By Nyquist theorem, I only can account half of the frequencies.
Assume I have a signal of length $N=100$, ...
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Data transmission through optical fiber and copper wire
I read the following in one reference: A copper wire (twisted pair), the link traditionally associated with low bit rate transmission, is still in use in the modern data centers transmitting data at ...
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Superposition of EM waves and "magic" behind tuned receiver circuit
I'm struggling to understand how the receiver circuit (eg. FM radio) is able to extract a particular frequency out of the sum of all received frequencies by its antenna?
I've checked dozen of websites,...
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Superposition of waves for changing frequency [closed]
Is this physically correct statement that the "superposition of waves increases with increasing frequency". An increase in frequency means smaller wavelength --> smaller path differences ...
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Why does not the speed of sound in air depend on frequency and wavelength? [duplicate]
I have read that speed of longitudinal waves depends upon the frequency and wavelength and, but why it doesn't happen with sound waves in air?
And if velocity of sound doesn't depend upon the ...
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How and why does a nonlinear element produce the sum and difference of two radio frequencies?
For a resonant circuit the voltages of the capacitive and inductance reactance cancel and the currents of the capacitive and inductance reactance also cancel leading to a zero reactance. Is there a ...
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What is the physics behind mixing two radio frequencies to produce the sum and difference frequencies?
In studying for my amateur exam I see the general equation $$f = n*f1 +- m*f2$$ where $m$ and $n$ are integers and $f$, $f1$, and $f2$ are radio frequencies. What are the physics behind that equation?
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I have seen people define frequency or amplitude in two ways, which one is correct?
I have a doubt on frequency and amplitude,I have seen people define these things in 2 ways,for instance, people define frequency in mainly 2 ways,if we draw a pressure-position graph of a sound wave,...
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Is it possible to control frequency of the light?
Generating light is the process of energy conversion. I mean is it possible to control the frequency of light by controlling directly the input like heat, current... not by filters or medium ...
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How do headphones and earphones produce good bass if tiny speakers can't produce low frequency sounds very well?
It's a well known fact that small/tiny speakers cannot produce low frequency sounds very well. Conversely, large speakers cannot produce high frequency sounds very well. Hence the need for tweeters ...
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What is the frequency of the sound?
Can someone tell me what is the frequency of the sound waves? Is it the number of compression or rarefaction going through in a second or the number of vibrations of the particles of the medium ...
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Dispersion laws
I am studying the dispersion law of the pressure $p(t)$ in order to obtain the wavenumber from the frequency.
In particular I am studying a discrete signal $p(t_{j})$. Once I have done the spectra $p(...
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How are sidebands generated in an AM signal?
I can't understand how sidebands get generated, even after reading this wikipedia page: https://en.wikipedia.org/wiki/Sideband#Amplitude_modulation
This is how I picture Amplitude Modulation in its ...
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Difference between wavelengths relation to frequency and period relation to frequency
I know that:
$\frac{1}{T} = f$
For some oscillation or sinusoidal wave. For instance, a period of 2 has a frequency of 1/2
And, in the physics I have taken the formula would be like the one given ...
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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 ...
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Why does density change the resonant frequency of a wineglass?
I’ve been looking at various sources, and they all say that density effects the energy transfer from oscillations of the wineglass (in other words, the heavier and denser the liquid, the more energy ...
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Taylor's hypothesis in turbulence
Reading about Taylor's hypothesis for converting spatial to temporal scales and vice-versa, I understand that if $V$ is the bulk speed of the fluid then we could use:
$$\ell = V \cdot \tau$$
To ...
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Is there any known result about the "average period" of a complicated oscillating function?
Say we have some frequency spectrum, $f(\omega)$, where
$$
f(t) = \frac{1}{2\pi} \int_{-\infty}^\infty d\omega \; f(\omega)e^{-i\omega t},
$$
and we know that $f(t)$ is some sort of ...
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How does amplitude affect frequency of a wave?
This is a fundamental question. I tried to find answers online but got confused. So, I'm asking here in hope of a simple and straightforward explanation.
Lets say we have a wave with amplitude x and ...
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