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

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470 views

Beat Frequency for Police Radar with Special Relativity

"A radar speed trap operates on a frequency $v_o = 109 Hz$. What is the beat frequency between the transmitted signal and one received after reflection from a car moving at v = 30 m/s toward the ...
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1answer
711 views

Why doesn't frequency change? [duplicate]

I've seen a mathematical example where a wave was made from same source in water and air. but in both medium frequency was same but wavelengths were different in each medium. we know that velocity of ...
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1answer
198 views

Explain why the frequency cutoff for RL circuits is given by $\frac{R}{2\pi L}$

I am studying low and high pass RL filters for Navy schooling. I need someone explain why the frequency cutoff is $fco = \frac{R}{2\pi L}$ mathematically. From my oscilloscope lab results I got the ...
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1answer
70 views

Spaceship Doppler frequency

A spaceship starts falling under gravity with an acceleration $g$ as measured by an observer Barry at rest on Earth. At the instant that the ship starts to fall, an astronaut Harry at the base of the ...
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1answer
337 views

Natural frequency of spring-mass system

We can found on internet videos or articles about resonance. For this they for e.g. take a system of two spring and mass in between. When they set force frequency to close to natural frequency. But ...
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1answer
274 views

Resonating frequencies of atoms

I have a mathematics and computer science background with very little physics. I have read that the resonating frequency of an atom of some element is always exactly the same as the resonating ...
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1answer
2k views

Calculating the energy of an electron given the wavelength

Okay, so I know that the wavelength of an electron is 5e-7m and I am asked to calculate its minimum velocity and hence minimum energy. Calculating the minimum ...
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1answer
317 views

Changing effective mass to lower frequency

I'm trying to scale a physical object up in size, either double or quadruple. It's a circular acrylic plate, with multiple weights attached around it's edge, to lower the resonant frequency to a ...
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1answer
64 views

Thinking Clearly about Fresnel Zone of Short Pulse:

Let's say you have a short pulse of light which expands radially from a lightbulb, and it impinges upon a mirror and reflects towards a photodetector which you have places somewhere above the mirror. ...
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1answer
427 views

Super High Frequency Electromagnetic Radiation - String Theory

I am a serious high school student with one year of physics class experience, so please point out if there are any flaws in my question or reasoning. Thanks! Gamma ray radiation possesses a ...
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2answers
2k views

Refraction of light and frequency dependence

Why do higher frequency waves refract more, both ocean waves and light waves? Also why is energy stored in the frequency as opposed to the wavelength.
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1answer
164 views

Will a photon emitted from something moving quickly have a shorter wavelength?

If a photon is emitted from a light source moving at any speed, the photon will nonetheless always move at c (assuming it is emitted in a vacuum.) If the speed of a photon's emitter cannot influence ...
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22 views

How does cavity resonance produce EM waves?

My understanding is it acts like a capacitor and inductor in a loop. The capacitor releases stored energy which is absorbed by the inductor through a magnetic field which then returns it to the ...
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1answer
22 views

Timekeeping , optical clocks, and precision

I am having trouble understanding something: The concept of time measurement. So I want to simply this as much as possible to get an intuitive understanding: We define the second by the time it ...
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0answers
12 views

Low frequency approximation

In the problem I have the function $$ K = B + \frac{A}{\omega} i $$ and it asks to make an approximation for low frequency ($\omega$). I tried Maclaurent series but I get $1/0$ because I have to ...
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0answers
26 views

How can frequency of waving in water change the direction object on the surface goes?

In an Australian experiment the physicists studied effects of a simple object that causes waves in fluid. They found that if it vibrates slow, the objects on the surface moves away from the vibration ...
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0answers
16 views

Book recommendations on physics of music and musical instruments [duplicate]

I am pursuing a degree in Mathematics and have a strong interest on music. I would like to understand the physical basis of how is music made. Does someone know some bibliography on this subject?
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27 views

Will decorrelating an audio signal help reduce interference patterns at low frequencies?

In live sound it is common to have a left/right sub-speaker configuration, which will produce an strong interference pattern in the audience area based on listener/sub-speaker locations. If the ...
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0answers
23 views

Sound frequency and power

Although I have studied physics I am not clear on this question: Given that two (or more) sound waves have the same amplitude does the power they carry depend on frequency? What about electrical AC ...
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1answer
40 views

Best frequency for Underwater Transmission

What is the best frequency of transmission of under the water for communication with good data rate? I have read that the threshold of hearing underwater is around 170 to 180 db. Can this be useful in ...
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22 views

What is frequency response of vibrating string? [duplicate]

If I transform wave equation for vibrating string Mx′′+Cx′+Kx=b(t) in linear system using $x_1(t)=x(t)$ and $x_2(t)=x_1^{'}(t)$ vibrating string equation becomes $Md_tx_2(t)+Cx_2(t)+Kx_1(t)=b(t)$. ...
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1answer
313 views

Tension of a string, based on Hz, string-weight and string-length [closed]

I’m not a physics student. Instead I have an electric bass guitar :) I know my strings vibrating-length: 0.800 Meter I know the total weight of this length: 0.016575 Kilo I know my strings resonant ...
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0answers
54 views

How would I calculate the frequency of the sound produced by a bowed glass plate?

I'm working on a project that involves getting a note to sound from a glass plate by bowing its edge with a violin bow. I'm trying to work out exactly what frequency I'll get from a piece of glass of ...
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1answer
31 views

Energy corresponding to the peak of velocity power spectrum

I ran a MD simulation for a number of N molecular hydrogen. I used the velocity time history of system for each atom and subtract the velocity of center of mass of each molecule from the velocity of ...
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75 views

Angular frequency integral to wavelength integral

I have this integral $$ \bar{\omega}^2 = \int\limits_{-\infty}^{\infty}\omega^2|\tilde{F}(j\omega)|^2\frac{d\omega}{2\pi} $$ and I want to convert it to wavelength domain $\lambda $. I know that the ...
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2answers
51 views

Interference of two waves of different frequencies relevance to background noise + sonometer

If two sound waves of different frequencies are recorded then does the interference between the two waves of different frequencies alter the resultant frequency recorded. In better context, I'm ...
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1answer
83 views

Gravitational “acceleration” and frequency change of a photon?

For massive particles, force translates into acceleration which again is a change of the velocity vector in direction and/or magnitude. For a photon, the velocity magnitude cannot change, only the ...
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1answer
3k views

Calculating half power frequency (frequency response)

I am having a doubt in calculating half power frequency for a given RLC AC circuit. I have attached images of two questions with their solutions. In the first question, the equation for ...
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0answers
446 views

Beat frequency for 3 waves

Consider 3 waves of frequency 101, 103, 106 hz, and of same intensity. What should be the beat frequency. Now I can calc it for 2 waves, and i know how to write the combined equation of the two. But ...
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2answers
459 views

relationship of number of standing waves with Temperature?

If we have let us say fixed air column of length 'L', in a open-closed column problem, lamba is equal to 4*L/(2n-1). n = number of nodes / anti nodes in air column How does 'n' changes with ...
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0answers
270 views

Minimum spread of frequency and wavelength in neodymium laser

What is the equation linking the minimum spread in wavelength and frequency of a pulsed laser, in relation to the lasers pulse time and operational wavelength. For example: If a Neodymium laser ...
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0answers
37 views

Unusual waves and one of its parameter

I'm messing up with this java app on the web about waves on a string and i'm really curious about something. The java app is the following : ...
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0answers
52 views

Ultimate Planck Frequency [closed]

Is there an upper limit to the Planck Frequency? Does it simply depend upon the inverse of the Planck Time unit?
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0answers
140 views

Frequency dependance of sound wave reflection

Why are high frequencies reflected more than low frequencies off an 'acoustically hard' surface such as concrete? I basically understand that the amount of reflection is determined by the impedance ...
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2answers
433 views

Rotational Velocity and Rotational Frequency

What is the difference between rotational velocity & rotational frequency? Their units seem to be the same, and I've read that one is a 'scalar' and the other is a 'vector,' but how do they ...
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1answer
88 views

measure higher frequencies then half of Planck-frequency?

The maximum frequency is defined by the Planck frequency $\omega_P$. Also there is the Shannon theorem which tells us that to lossless capture a signal, you have to sample it with minimum of the ...
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5k views

Light traveling through a medium

Does the frequency of light change when it travels across an interface between two media? What happens to the light wavelength and the light velocity at the interface? I've gotten different answers ...
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1answer
1k views

How would natural (resonant) frequencies affect amplitudes?

I read $y=A\sin(2\pi ft)$, where $A$=Amplitude, $f$=Frequency, $t$=Time and $y$=$Y$ position of the wave. Since natural frequencies only take the most effect when they are close to the frequency. How ...
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242 views

How do you super impose two or more signals to occupy a fix area of space with the resultant summed wave?

Is it possible to super-impose two or more signals all sent from different directions as a standing wave with the resulting summed wave occupying a fix area of space that is also a complex area? Do ...
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0answers
81 views

What phenomenon is responsible for the evolution pattern of waves created by waterfalls?

I have been fascinated lately by the pattern of the waves created by a waterfall in my town. Specifically, the pattern shows a gradual decrease in the density of the waves as they travel away from ...
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1answer
926 views

Relationship between classical electromagnetic wave frequency and quantum wave function + de broglie frequency

As it is. As I study through classical mechanics and quantum mechanics, I began to wonder whether there is a relationship between classical electromagnetic wave frequency and quantum wave function ...
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3answers
108 views

How can frequency be constant during refraction? [duplicate]

When entering from a rarer to a denser medium, the speed of light decreases.I know that the frequency remains constant.But if frequency is cycles/sec then doesn't that mean more speed will lead to ...
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2answers
81 views

What is energy of light, as we know speed of light?

1.What is total energy of EM waves, as all got same speed? If two em waves has same energy, do they have same mass? If same mass and energy, do they have same frequency or wavelength still ...
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3answers
5k views

Intensity of light

If we have 2 beams of light with equal intensities, but with different frequencies, wouldn't the one with the higher frequency generate more power? If so, how come the intensity, which is in $W/m^2$, ...
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3answers
534 views

Why is 'the period' marked as letter T?

I'm not a native English speaker and I was wondering, why 'the period' got the letter $T$. I've asked myself the question when I was thinking about stuff related to the frequency. I.e.: $f$ - ...
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3answers
2k views

Doppler effect “apparent frequency”

In discussing Doppler effect, we use the word "apparent frequency". Does it mean that the frequency of the sound is still that of the source and it is some physiological phenomenon in the listener's ...
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2answers
3k views

Can the equation $v=\lambda f$ be made true even for non sinusoidal waves?

The known relation between the speed of a propagating wave, the wave length of the wave, and its frequency is $$v=\lambda f$$ which is always true for any periodic sinusoidal waves. Now consider: ...
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1answer
45 views

Why doesn't frequency of a sound wave reduce with time?

I understand how energy depends on amplitude as this source says but this source mentions that the energy of a sound wave depends (maybe "also on") on frequency of the sound wave. If energy of a wave ...
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2answers
72 views

Could a single impulse be classified as a sound wave?

If not, how many counts(cycles) of impulses are needed before we can call it as sound(without 20-20000Hz limit)?
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5answers
72 views

Dependence of Color of Light on Wavelength?

Recently i saw a question here which asked "what does the color of light depend on as we percieve it?".Now some members answered that if you see an object from any other medium it appears the same ...