Questions tagged [frequency]
Frequency is the rate of repetitive aspect in the amplitude over a given dimension.
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Is light a single wave when we refer to frequency?
When we say that light oscillates $n$ times (frequency) in a second do we mean that the same electromagnetic field travelling through space oscillates $n$ time's? As i have seen diagrams suggesting ...
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Frequency of superimposed wave
If two waves with frequency $f_1$ and $f_2$($f_1≠f_2$) are added together to form a superimposed wave then what will be the frequency of the resultant wave if -
the velocity of the two wave is same
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When we shrink a box containing a gas does the increased fraquency of molecules impacts on the box cause the rise of its temperature?
When we shrink a box containing a gas does the increased fraquency of molecules impacts on the box cause the rise of its temperature?I assume the kinetic energy of the molecules shouldn't change ...
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50 mhz signal pulsed at 4 khz [closed]
a 50 mhz signal pulsed at 4 khz can be received by a 20cm antenna. That is, since they are pulsed at 4 khz, the antenna receives them ??
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Doppler Effect formulas for stationary observer and source [duplicate]
I am a high school student and recently learnt about the doppler effect. My teacher showed me two different formulas for the doppler effect with moving observer and moving source. Why are there ...
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The same frequency sounds sound as different sounds
Imagine, the piano is sounded $500 \mathrm{Hz}$ sound and the same frequency is sounded in a violin. We always observe their sounds are different even though they're harmonic.
I think there must be ...
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What is the wavelength of white light? [closed]
Does white light have a wavelength, and I know that the sun emits white light, but the atmosphere makes it refract to make it appear yellow to us. Do all the stars in the universe emit white light?
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Can the wavelength of light change after it is emitted in a vacuum? [closed]
Can the wavelength of light change after it is emitted in a vacuum?
As the picture below describes, is it possible for light to change wavelengths after being emitted in a vacuum (no medium).
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Can a X-ray photon increase its frequency after scattering of a nucleus?
Can a X-ray photon increase its frequency after scattering of a nucleus? Let say nucleons are oscilating inside a nucleus due to interaction between residual SNF and Coloumb force... Can this ...
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Spring-mass system in an elevator
I have a conceptual doubt.
If we have a mass m hanging from an ideal spring, attached to the ceiling of an elevator... what happens to the period if the elevator starts going up or down with constant ...
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Why refractive index of same material is different for different monochromatic lights?
Yeah I know that refractive index is different for different monohromatic lights due to the change in velocity of light. And as frequency doesn't changes and only wavelength changes while travelling ...
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Stationary Nodes with Waves containing a "Fourier series" of frequencies
For a standing wave (i.e. a wave pattern created from two oppositely-traveling waves with the same amplitude and frequency), stationary nodes are created at certain positions along the wave with ...
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How to find frequency response of a damped spring mass system using the Laplace transform
I would like to find the frequency response of a spring mass system of multiple degrees of freedom by using the Laplace transform. I think I know how to do this with one mass oscillating, however I ...
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Planck's quantum theory
Recently came across Planck's theory, $E = h\nu$.
It means that at any frequency, there is given energy. But I also saw that, $E$ can be $0, h\nu, 2h\nu, 3h\nu,...$.
How is it possible that energy can ...
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What is the relation between the frequency vector and the Nyquist frequency?
When trying to comprehend the concept of Nyquist frequency in FFT, I came across the following definition for half of the frequency range:
$$f = -f_{n}/2:df:f_{n}/2-1;$$
where $f$ represents the ...
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Can a metal sheet roof be vibrated at audio frequencies?
So I'm renting a cheap place for now due to certain circumstances. Problem is outside noise is excessive because there is no ceiling and the roof is only a metal sheet... Lately I play white noise to ...
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Upper limit of energy carried by one photon [duplicate]
energy carried by one photon, $E = hυ$ where $υ$ is frequency and $h =$ planck constant. Is there any upper limit to how much energy one photon can carry? or any upper limit of frequency?
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Why does amplitude modulated wave take the frequency of a carrier signal when passed through air?
If a message signal of frequency $f_m$ is amplitude modulated with a carrier signal of frequency $f_c$ and radiated through an antenna, the wavelength of the corresponding signal in air is
ans: $\frac{...
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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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Factor of two when finding the number of AM stations which can be fit into a bandwidth given the highest modulating frequency
How many AM broadcast stations can be accommodated in a 100 KHZ bandwidth if the highest modulating frequency of carrier is 5 kHZ?
Ans.
Solve by using the formula:$$ \text{total band width}= 2 ( \text{...
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The energy of the photon $hf$, so what is the energy of other masses such as the Earth?
The energy of the photon $hf$, so what is the energy of other masses, and of course I do not mean to write in frequency $f$, what is the relationship of the energy of other masses
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Definition of boundaries within the electromagnetic spectrum
As far as I know, there are no universally accepted boundaries within the EM spectrum. This means that different authors will provide a different frequency or wavelength to separate the different ...
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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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Why do optical phonons have such a high frequency at $k=0$?
Can you give me some intuitive explanation of this? How is there any frequency when wavelength becomes almost infinite?
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Standing Waves: question on guitar string behavior [duplicate]
Wiki shows the fundamental and first overtone frequencies as follows. I'm trying to relate these to a vibrating guitar string and interference. I'm assuming these animated images represent the ...
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How to find out resonance frequency of micro-resonators?
I am a student with a theoretical background, so I'm not well versed in the practicals. I have, on a silicon chip, a vacuum gap capacitor of Nb of 5 microns x 20 microns dimensions with 500 nm gap ...
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Find the frequency of the first two harmonics of a vibrating string
I have a string of length $2 \;\text{m}$ and the wave velocity is $120 \;\text{m/s}$, find the frequency of the first two harmonics.
My attempt, what I must do is to solve the wave equation on the ...
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What causes the undistorted propagation of picosecond THz pulses not to be possible for circular waveguides?
When reading about the concept of circular waveguides, I came across the following statement that I am struggling to undertand.
"(...) for circular waveguides the undistorted propagation of ...
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1answer
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Shortest wavelength of sound wave in solids
In the book Thermal Physics by Schroeder, it is mentioned that "sound wave in solids cannot have wavelengths shorter than twice the atomic spacing". I am wondering if this is related to ...
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2answers
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How things appear to naked eyes at very high frequencies?
We know after a certain frequency our eyes cannot see the changes but how to predict what should be the steady state appearance (of things changing at much higher frequencies )seen by the eyes ?
For ...
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Faraday Cage - Wavelength and hole size
I read about the faraday cages and understood that the size of the holes should be very small than the wavelength of the signal for effective shielding.
But I am really confused due to the ...
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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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What does the amplitude of a light wave tell us? How's it different from light intensity in a physical sense?
In my understanding, the energy of a photon, in wave terms, just translates to the frequency of the wave. If I make a photon with more energy, it will use the extra energy to just oscillate faster.
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How to derive group velocity dispersion (GVD)?
I'm trying to arrive to the following expression to group velocity dispersion:
$$\text{GVD} = \frac{\lambda^3}{2 \pi c^2} \frac{d^2n}{d \omega^2}.$$
I know that GVD can be expressed as:
$$\text{GVD} = ...
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Graph Interpretation of Gravitational Waves
In the image is the data recorded by the LIGO's 2 observatories in USA. What is its interpretation? I mean what does the zig zag lines represent? Similarly, what does the blond red and blue lines (...
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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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Why is a subwoofer bigger than a tweeter? [duplicate]
I came across this video - The Fundamentals of Sounds - where it says in 14:00:
Subwoofer is larger because it needs to be bigger for those larger low
frequency waves to propagate through and the ...
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1answer
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Do different frequencies move at the same speed with a given medium?
According to this website, it talks about plate reverbs with the characteristics of their sound. However, I have highlighted the section that confuses me as it states that:
So, my question is:
Aren’t ...
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Dealing with Larmor frequency fluctuations for $\pi/2$ pulses
I am currently facing the following experimental problem:
I can currently measure the $z$-components of a spin assembly after a $\pi/2$ pulse:
The static B field is along the $z$-direction and with a ...
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1answer
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How does changing the mass affect both the amplitude, and frequency of said mass when a sinusoidal force is applied
Lets say you had a 100g mass bonded to a vibrator which applies a force up and down. It is known that at 100g this mass would oscillate at a maximum pk-pk acceleration of about 5G's, and at a ...
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2answers
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Frequency dependent resistor
I'm trying to create a real impedance that goes like 1/$\omega$, that is - a frequency dependent resistor (without imaginary part).
Is it possible at all? If not, is it possible at least on partial ...
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2answers
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Problem with spring oscillator measurement - inconsistent frequency
I measured the periodic movement of a spring with a mass and plotted it
Looking at the first graph, I assumed the frequency is somewhere between 2-2.5 Hz.
The mass hanged on spring was 100 g. Using ...
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1answer
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Is there a finite number of colors in the visible spectrum? [duplicate]
Does quantum theory and Planck's length of $1.6\times10^{-35}\ \mathrm{m}$ mean that the electromagnetic spectrum is not continuous as every photon can only carry a discrete amount of energy?
If so, ...
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1answer
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Is photon a wavepacket of electromagnetic field?
Photon is a "particle of light". Light is just a propagating EM field. Therefore photon is (at least intuitively) a localized EM field (i.e. wavepacket).
In quantum optics, the Hamiltonian ...
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What is the difference between $v=fλ$ and maximum velocity in the formula $v=ωY_{\max}$? [closed]
I was wondering what the difference is between speed in the formula $v=fλ$ and maximum velocity in the formula $v=ωY_{\max}$ as applied to a wave.
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Change in refractive index due to the acousto-optic effect, and the use of acousto-optic modulators for the sole purpose of frequency shifting
Chapter 3 Acousto-Optics of the textbook Crystal Optics – Properties and Applications by Ashim Kumar Bain says the following:
In general, acousto-optic effects are based on the change in the ...
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What is the meaning of the absolute of the Fourier transform in this context?
In a course talking about Fourrier transform and Nyquist frequency, there is this sentence that I can't understand:
"If a signal has $|F(w)| \geq 0$ only for frequencies till f, than such ...
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1answer
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Why can harmonics be a different note than their fundamental frequency?
I was under the impression for the longest time that when you hear a harmonic on a string, its basically a sum of different resonating frequencies, which are all INTEGER multiples of the base ...
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2answers
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Doubt on the predictions on the photoelectric effect according to the wave theory of classical physics
I read in some texts that classical physics predicted the following in the photoelectric effect,
KE of electrons ejected is directly proportional to intensity of
light
Increasing the frequency would ...
