Frequency Definition and 1000 Threads

Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as temporal frequency to emphasize the contrast to spatial frequency, and ordinary frequency to emphasize the contrast to angular frequency. Frequency is measured in hertz (Hz) which is equal to one event per second. The period is the duration of time of one cycle in a repeating event, so the period is the reciprocal of the frequency. For example: if a newborn baby's heart beats at a frequency of 120 times a minute (2 hertz), its period, T—the time interval between beats—is half a second (60 seconds divided by 120 beats). Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light.

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  1. Lahearle

    I How can I estimate the K force constant for bond types without special tools?

    Hi I'm trying to throw together a cool chart, I need the K constant so I can divide K/U to get the CM-1 measurement of every element for every bond type. I don't have any special tools for this, no force gauges. Does anyone have any idea how to at least roughly get an accurate depiction of...
  2. Lahearle

    Please Help with bonding frequencies

    Hi I need all the bonding frequencies for all the elements in the human body, IE: carbon-carbon single bond frequency of 1300 cm - 1. It is very important to have the single, double and triple bonds because I am doing something that will require them all. It would also be helpful if someone...
  3. S

    I Find the "ringing" frequency from sum of multiple overlapping transients

    I am looking for an algorithm that will get the best estimate of the ringing frequency of a system subjected to impulse excitations at random times. The individual responses might look like this: And the total which I would like to analyze would be like:
  4. Agent Smith

    B What Defines a 2-Way Frequency Table?

    Has dogs Doesn't have dogs Total Has cats 3 5 8 Doesn't have cats 4 1 5 Total 7 6 13 The course I'm taking says the above is a 2-way frequency table because there are 2 categories: cats and dogs. So the table below is not a 2-way frequency table? Men Women Children Total Ate...
  5. J

    Op Amp with frequency compensation input

    Does anyone know of a modern op-amp (available) with a frequency compensation input as the very old 709 had?
  6. P

    Doppler Effect Question: Flying Bat Echolocating a Mosquito

    Hi, Would 1) be f' = (10,300)[(340 - 1.00) / (340 - 1.05)] = 10,302 Hz 2) f' = (10,300)[(340 - 1.00) / (340)] = 10,270 Hz 3) Yes? As the frequency changes more and less than 1.00 Hz. I am unsure and would appreciate any help. Thanks!
  7. pallab

    I am trying to stabilize laser frequency with PID controller

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  8. N

    Colour depends on wavelength or frequency?

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  9. S

    Small alarm system circuit analysis

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  10. DaveC426913

    B Predicting frequency of Earthlike planets and systems

    Each new report of a confirmed exoplanet adds to the database of knowledge. For obvious reasons, our confirmations seem to stack up in the areas we are currently best able to detect. eg.: Large bodies: Jupiter-sized down to Sub-Neptune-sized, with a smattering of super-Earths. Nape-of-star...
  11. S

    Ratio of frequency between heavier and lighter part of composite cord

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  12. S

    Concept about photoelectric effect

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  13. S

    Range of frequency heard by observer related to Doppler effect

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  14. E

    B Sine wave noise at different frequencies

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  15. M1N

    Calculate the frequency of rotation when a coin flies off a turntable

  16. M

    B How Fast Do Different Atoms Vibrate?

    The "ticks" of the current standard atomic clocks are marked by the regular vibrations of an ensemble of cesium atoms, which vibrate 9.2 billion times every second How about other atoms, how fast does these vibrate ? And where is possible to ready about this ?
  17. S

    I Is nonlinear acoustics in mainstream physics?

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  18. Q

    I Why is Photon Energy Quantized in Terms of Sine Wave Frequency?

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  19. L

    Comp Sci Use a simulator to produce a resonance curve for this RLC circuit

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  20. N

    I Relationship between frequency and power for sound?

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  21. S

    Why is there are precession frequency here?

    so I need to use the eq.: omega_pr = ##mgr / L_s## with r = 6cm. But from how I imagine/see it, the rod pierces the disk through the middle so how does this create precession if the weight will not cause a torque then and thus a hortizontal change in angular momentum? Thanks in advance!
  22. K

    I What Determines the Use of Normal vs Angular Frequency in Quantum Transitions?

    This might be silly, but I am a bit confused by the conventions used for transitions in atoms/molecules. Usually these are given in nm and using the formula ##\lambda = c/\nu##, from here we can get the normal frequency ##\nu## and the angular frequency would be given by ##\omega = 2\pi\nu##. In...
  23. M

    Moving Source, Observer at Rest, derivation for Doppler effect

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  24. S

    B To measure light's frequency, do we interact with each crest + trough?

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  25. Sagittarius A-Star

    I Mass of Electron & Flipping Frequency: Leonard Susskind Explains

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  26. A

    Engineering Short vs Open Circuit: Is That Correct?

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  27. patric44

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  28. H

    I Does an electron have a quantum phase frequency?

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  29. garryA

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  30. B

    High power RF amplifier at fixed frequency

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  31. Mustafa Bayram

    B Is there a fractional frequency of light?

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  32. Darmstadtium

    I Relationship between the Different Frequency vs Decibel Graph Peaks

    In the popular answer for the coin-mass question of Physics Stack Exchange, I am wondering what are the correlation between the first red peak at around 9kHz and the second red peak at 16kHz. I first thought that they are consecutive harmonics but there was no way of proving it as I do not know...
  33. LarryS

    Formula for Resonant Frequency of 2 Metal Coaxial Cylinders?

    Consider an LC circuit consisting of a parallel plate capacitor and a solenoid inductor in series. The formula for the resonant frequency of this circuit is 1/√(LC) where “L” is the inductance of the solenoid and “C” is the capacitance of the capacitor. Now consider a high-frequency cavity...
  34. homeworkhelpls

    How is Wave Intensity Affected by Half Amplitude and Double Frequency?

    TL;DR Summary: How do i find the intensity of this wave? I know I is proportional to amplitude / frequency squared, but I don't know what equation this comes from. And I don't know how to answer this.
  35. abdulbadii

    Transformer frequency contradiction on induction heating

    As a transformer freq bet higher, inside induction get more efficient i.e. less loss: 1. Hysteresis loss = η * Bmax^n * f * V. 2. Eddy current loss( proportional to B2mf2Bm2f2 )Now it seems that losses increases with increase in efficiency... But the above equations are valid when max flux...
  36. T

    I Frequency of prime number gaps according to (p-1)/(p-2)

    Caution I'm not a mathematician. In short, long time ago I calculated prime number gaps just for fun expecting an almost uniform distribution of the frequency of the gaps 2, 4, 6, ... . Instead the frequency showed a series of maxima and minima and I was confused. Later Professor emeritus Oskar...
  37. U

    Spring first natural frequency and hysteresis

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  38. S

    B How Can We Resolve Noise from Low Frequency Quanta in Electromagnetic Waves?

    What is the lowest frequency/energy where photons have been observed? That is, electromagnetic waves observed as quanta, not continuous waves? Resolving noise that is not thermal noise, not shot noise from the discrete nature of the electrons in the receiving electronic, nor from the...
  39. sinus

    I Question about Waves -- "frequency" versus "angular frequency"

    I've been reading many references that said "frequency" and "angular frequency" are two different things. I'm writing a report about damped oscillations experiments (that's a task from a subject in my college). Can someone tell me which one is the resonant frequency (natural frequency)? f or ω...
  40. A

    I'm getting two possible uncertainties for frequency

    Calculate the speed and uncertainty in the speed for a wave with wavelength ##50\pm 3\mu s## and frequency ##30\pm 1kHz##. Also calculate the period and uncertainty in the period. I am not sure about my answer to the second part. I used propagation of errors to get ##\Delta...
  41. S

    Derive angular frequency for mass spring system

    tried writing the x position as x = Acos(wt) (ignoring the phase) so that d2x / dt2 = -w2x Substituting that into the individual motion equations would get the required result for the individual masses, but I am not sure how to combine the equations to get the reduced mass
  42. bobacity

    Wave Period Calculation: Is 0.1 the Correct Answer for Frequency of 1/10?

    I think the answer is just 1/10 (according to the formula for period), so the answer is 0.1. Is that correct? Thanks!
  43. bobacity

    Calculating Speed of a Wave | Solving Problem with Period of 0.025s

    Since the period is 0.025s, I think the frequency is 1/0.025s = 40 Hz. I don't know how can I proceed solving the problem from here. I'm assuming I will have to try to find the velocity and wavelength, but idk how.
  44. bobacity

    Solving Simple Oscillation Frequency: A Quick Guide

    I think I can solve the frequency by doing 1/0.400 μs, but I'm not sure.
  45. A

    Beat frequency heard from two tuning forks

    Is my solution correct? I used v=lambda*f, i.e. f=v/lambda to get the frequency for each wave. Then I calculated the average of the frequencies to get 258Hz and found the beat frequency by doing f1-f2 to get 4Hz. I then said that this means the observer will hear a tone of frequency 258Hz which...
  46. Ahmed1029

    I Wave number, frequency, and velocity in dispersive waves

    1) If I generate a dispersive wave, will it have well-defined constant wave number and frequency? Ones that don't change in time? 2) does the velocity of any point on the wave stay constant in time? 3) How does force interact with waves? Does a free wave act in analogy with free particles...
  47. H

    A Realizing EIT with Pulsed Laser: Intensity, Duration & Frequency

    I have realized EIT with continuous laser. What are the requirements for the intensity, duration and repetition frequency if EIT is realized with pulsed laser? you can attach any reference:biggrin:thanks a lot!
  48. N

    Converting centrifugal acceleration to frequency

    I've calculated this. Is it correct? a=ω²R => ω=√(a/R) T(period)=1/ω=1 / (√(a/R)) f = 1/T = √(a/R) [ if a=10G=100 m/s² ; R=1m ] then: f = √(a/R) = √(100/1) = 10 hertz In angular velocity, can I just convert a=ω²R to ω=√(a/R) and write instead of ω=(2π)/T (in the first line)?
  49. M

    B High Frequency Photons: More Mass, More Bend?

    Since high frequency photons have more relativistic mass, should we expect them to bend more than lower frequency lights when traveling through a gravitational field, thus produce a rainbow effect? But we don't seem to experience rainbow effects with star light.
  50. R

    B Is it possible to get the photoelectric effect in red color frequency?

    Is it possible to get the photoelectric effect in red color frequency?
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