Questions tagged [frequency]
Frequency is the rate of repetitive aspect in the amplitude over a given dimension.
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Convert wavelength bandwidth to frequency units [closed]
I understand that $\Delta\nu=c\cdot\Delta\lambda/(\lambda^{2})$ from the derivation of $d\lambda/d\nu$. However, I don't see why as the central wavelength $\lambda$ increases, $\Delta\nu$ decreases ...
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Units conversions between rad/s to Hz [closed]
I was under the impression that Hz = 1/2pi rad/s, when dealing with spring-mass oscillation and its natural frequency.
However, I was marked down for this conversion, and I don't know if I'm just ...
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I don't understand intuitively why the instantaneous frequency is obtained by calculating the time derivative of the phase
I don't understand intuitively why the instantaneous frequency is obtained by calculating the time derivative of the phase
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Does sunlight have a modulation frequency?
By frequency, I don't mean electromagnetic frequency, I mean modulation frequency. For example, I can put a PWM square wave on an LED at some frequency, which I can detect with a photodiode and a ...
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What's the difference between the different kinds of EM waves?
I am an A-level student.
We have traditionally been taught that different types of EM waves exist only between certain ranges of wavelengths and frequencies.
However, I learned that electromagnetic ...
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Why do we see objects with a given color?
I'm currently studying Electromagnetic Optics, and I don't quite understand the (classical) process through which we perceive an object with a given color. From my understanding, I'd make a ...
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Who wrote $c = λ ν$ for the first time and where can I find it?
I have been surfing for days and still I could not find who wrote the equation $c=λν$ for the first time. Neither I found a name for this equation. A lot about Planck's constant and energy related ...
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General formula for the frequency
The orbital period of a satellite is the time it takes to complete an entire orbit around the celestial body around which it orbits. I know that the orbital period using the following formula:
$$T = \...
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Why Does Planck's Relation $E=hf$ Imply a Linear Relationship Only for Sinusoidal Frequency Bases?
I have been studying quantum mechanics and I came across Planck's relation which describes the energy $E$ of a photon as being directly proportional to its frequency $f$, with Planck's constant $h$ as ...
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Why are laser linewidths in frequency domain?
I am learning about the lasers and I find one thing confusing about the lasers.
I understand that there is a range of wavelength laser, it is never exactly monochromatic. So, I understand the concept ...
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Why color depends on frequency and not on wavelength? [duplicate]
To explain my question lets consider this example:
The wavelength of light in a medium is $\lambda=\lambda_{0}/\mu$, where $\lambda_{0}$ is the wavelength in vacuum. A beam of red light ($\lambda_{0}=...
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Why do water surfaces have persistent "average wavelength" patches?
Have you ever stood above a river or lake and noticed that the surface has visible "patches"? It looks like the surface has different average wavelengths in some areas, leading to the light ...
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How can the Rabi frequency be complex?
I've been doing some reading and came across a simple implementation of the Hadamard gate using Rabi oscillations of an atom in a laser field. However, the author mentions that it required the Rabi ...
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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 ...
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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 ...
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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$. ...
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Orbital frequency of gravitational wave prior to merger [closed]
In the paper The basic physics of the binary black hole merger GW150914
Equation [A5] states that
$$\dot \omega^3=\left(\frac{96}{5}\right)^3\frac{\omega^{11}}{c^{15}}\left(G\mathscr M\right)^5
\tag{...
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Frequence vs speed of a moving object
Imagine swinging wood stick using hand (say it's a 1-meter long cylinder with 2 centimeter diameter, just for the sake of argument). When doing it fast (angular velocity = $\omega_1$), it will create ...
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Damped Quantum Harmonic Oscillator with sinusoidal driving force
The standard Damped one-dimensional Harmonic Oscillator with sinusoidal driving force has equation
$$\frac{d^2}{dt^2}x(t)+2\zeta\omega_0\frac{d}{dt}x(t)+\omega_0^2x(t)=\frac{1}{m}F_0\sin(\omega t).$$
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Measuring the tension of a drumhead
I'm working on an experiment to see how the tension of a drumhead impacts the frequency of its sound, but I'm not sure as to how I could measure this.
I found this forum thread from 2012, which ...
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How to standardize the energy of a Dirac delta function relative to sample rate (width) and amplitude?
Background
I was instructed that a Dirac delta function (impulse from $0$ to $A$ then back to $0$ at short duration) has a white noise audio frequency type excitation distribution here
ie. It should ...
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Is it possible to, like white noise, excite all audio frequencies equally, but with a more immediate & less random burst? Like a signal discontinuity?
I am trying to generate an audio signal that, like white noise, has "equal intensity at different frequencies, giving it a constant power spectral density", but unlike white noise, can be ...
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What is the spectrum of a broken square drum?
Given a square drum with sides length equal to $L$, the squared raised frequencies are
$(\pi m/L)^2 + (\pi n/L)^2 $ with $m,n \in \mathbb{N}^*$.
Here we have four boundary conditions (no vibration on ...
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Why doesn't frequency change when the medium of the wave changes, and only depend on the source of the wave? [duplicate]
When the medium of the wave changes, the velocity and the wavelength does change, but not frequency, why?
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Do humans hear the beat frequency or the average frequency or just individual frequencies?
We have two sound sources of the same amplitude but of slightly different frequencies : $f_1$ and $f_2$. When they are sounded simultaneously what would be the frequency that an observer hears ?
I ...
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Why does the equation of a wave contain the term $\omega t$ instead of $vt$ in the wave equation $y=A\sin (kx-\omega t)$?
Why does the equation of a wave contain the term $\omega t$ instead of $vt$ in the wave equation
$$y=A\sin (kx-\omega t).$$
I think of the constant $k$ which for higher values increases the frequency $...
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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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$0$th overtone in closed organ pipes
I know about $1$st, $2$nd or other overtones in the formula of frequency in a one-sided open system (specifically in closed organ pipes) that is
$$ f = \frac{\left( 2 n + 1 \right) v}{4 L} \tag{1} \...
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Let's say I have manufactured a prism from a non-dispersive medium, then light coming from air wouldn't split into colours right?
Let's say I have manufactured a prism from a non-dispersive medium, then light coming from air incident on the prism wouldn't split into colours, right? I mean light still changes direction, but all ...
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Generally speaking, the speed of a wave depends on the medium and the wave type, so waves of the same type in the same medium attain the same speed [duplicate]
My question is, given the above statement, why electromagnetic waves attain different speeds in media other than vacuum even though they are of the same type and propagate in the same medium?
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A ball dropped onto a rotating wheel of various frequencies experiment issues
I'm doing a experiment to find the relationship between the frequency of the rotating wheel and the horizontal distance travelled by the ball dropped onto it. I am manipulating the frequency of the ...
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How do lower frequencies change differently than higher ones as they travel?
I read the following on the internet:
"This means that as sound travels, its relative frequency content alters making the low frequencies more prominent at greater distances, creating low ...
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Number of times the displacement of an object executing a simple harmonic motion becomes zero
I was solving some SHM problems when i came across this particular question. It asked, what is the frequency of SHM of an object whose displacement becomes zero 200 times in one second. The answer is ...
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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 ...
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The physics behind the circle / spiral of fifths
In music theory, there is this thing called the circle of fifths.
If you take a string, and you divide it in two equal parts, you get a so called octave. It is, to our ear, kind of "the same tone&...
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Can human ear hear 4 Hz frequency, if I tap my hand 4 times per second on table?
Frequency means the number of repetitions per second. Humans can hear between 20 Hz and 20 kHz, but I have a very basic question: if I tap my hand four times on a table per second, it means I am ...
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Change in Frequency while Tearing Paper
Let us assume you have a 30cm strip of paper, and you tear it lengthwise. Let us abbreviate the frequency produced when you reach the end of the paper as $f_2$ and the frequency of sound heard when ...
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Is sound essentially motion?
From my understanding, the only way for humans to create sound is by moving our bodies, vocal cords, or by moving other objects. So depending on how fast we or other objects can move, different ...
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Why doesn't the frequency of a cyclotron make an impact on the radius of the path of a charged particle?
The cyclotron frequency is given by $$f=\frac{qB}{2πm}$$
Obviously this equation has nothing to do with the radius.
But my question is, when the frequency increases, shouldn't the velocity increase, ...
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How can I find if it is gold or lead with waves? [closed]
I would find if a bowl is made of lead or gold know freqencies $w_{1}$ and $w_{2}$ and a vibrator induces waves at $z=0$ (and there are reflected waves). I do it with progressive plane electromagnetic ...
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Does dimensional consistency imply the same units?
Can two units having the same dimensions always be used interchangeably? For example $s^{-1}$ and $\frac{rad}{s}$ have the same physical dimension, does that mean we can measure frequency $\nu$ with ...
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Translating plasma units into SI units
I am trying to compute the characteristic lengths and frequencies in a plasma, namely the electron plasma frequency and electron inertial length. From the NRL plasma formulary
$$\omega_{pe}\ [rad/s] = ...
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The frequency is off by a factor of $2 \pi$?
I was reading Morin's Introduction to Mechanics, and the following material came up:
At equilibrium point $x_0$ expanding the Taylor series, we see $V(x)=\frac12 V''(x_0)(x-x_0)^2$ so comparing this ...
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What is the angular frequency $\omega$ in which the maximum current occur?
for a circuit which consist of an AC supply, an inductor, a resistor and a capacitor, the differential equation would be $IR+V_C-V_0 cos(\omega t)=-l\frac{dI}{dt}$.
Taking another derivative with ...
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How to Measure Energy of a Electromagnetic Wave accounting also for frequency?
We know a way of measuring energy of a electromagnetic wave is the Poynting vector, which is independent of the frequency. But let's say we want to make two different electromagnetic waves, with ...
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How do you extrapolate frequency data from FDTD simulation time data?
Context: Im a PhD student who plans on doing research in theoretical plasmonics/nanophotonics, so I am studying up on understanding FDTD. I am having a bit of a conceptual issue regarding ...
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How does a string thickness affect the frequency of its harmonics?
The harmonics of a theoretically infinitely small diameter string are pure integer multiples of the fundamental frequency. However, a real string has a thickness, and when vibrating in a harmonic, the ...
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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 ...
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Piezoelectric circular plate resonant frequency
I was trying to make a project where I was using piezoelectric. I gave him vibration by making some noise around here, and when I saw the output at DSO, it showed me 49 Hz. but I need resonant ...
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Does our sense of color depend on frequency of source or the wavelength of light?
I was taught that the colors we see are results of the corresponding wavelength, but each wavelength also has a distinct frequency since speed of light is fixed for a specific medium (same goes for ...
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