What is Wavelength: Definition and 1000 Discussions

In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, troughs, or zero crossings, and is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns. The inverse of the wavelength is called the spatial frequency. Wavelength is commonly designated by the Greek letter lambda (λ).
The term wavelength is also sometimes applied to modulated waves, and to the sinusoidal envelopes of modulated waves or waves formed by interference of several sinusoids.Assuming a sinusoidal wave moving at a fixed wave speed, wavelength is inversely proportional to frequency of the wave: waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths.Wavelength depends on the medium (for example, vacuum, air, or water) that a wave travels through. Examples of waves are sound waves, light, water waves and periodic electrical signals in a conductor. A sound wave is a variation in air pressure, while in light and other electromagnetic radiation the strength of the electric and the magnetic field vary. Water waves are variations in the height of a body of water. In a crystal lattice vibration, atomic positions vary.
The range of wavelengths or frequencies for wave phenomena is called a spectrum. The name originated with the visible light spectrum but now can be applied to the entire electromagnetic spectrum as well as to a sound spectrum or vibration spectrum.

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  1. J

    Wavelength and laser basics (ND:YAG)

    Hey guys! I hope my English skills are enough to describe my problems sufficiently.(Homework Statement ) I. Following the following picture, what wavelength should a laser be used to process aluminum? II. What metal surface can be cleaned with a frequency-doubled NDYAG laser? To I: The...
  2. S

    B If energy increases with decreasing wavelength, then...

    ..then a wavelength of zero nanometers has infinite energy?
  3. G

    I Gamma radiation, photon energies and wavelength question

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  4. N

    Experiment - Flux, Irradiance, wavelength from Temperature

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  5. B

    I DeBroglie wavelength & particle-wave duality

    We are told to exorcise wave-particle duality because it belongs to the past, in fact prior to 1927. So it’s acceptable to believe matter is neither wave nor particle. But in exorcising wave-particle duality. Why does the deBroglie relationship of momentum being inversely proportional to...
  6. snate

    I Large wavelength and "fitting into" small spaces

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  7. weezy

    I A question about a particle's de Broglie wavelength

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  8. S

    Amplitude and wavelength of longitudinal wave

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  9. RJLiberator

    What does Wavelength have to do with Crustal Structure?

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  10. Adam Rabe

    How to calculate wavelength electron given speed

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  11. D

    What Is the frequency of red light?

    Homework Statement The speed of light in a vacuum is 3.00x(10*8)m/s. Using the equation v=fxλ, calculate the frequency of red-light. (I was told to use the wavelengths given from textbook) Wavelength/λ =700nm v=300,000,000 <-- ( I need help understanding this. Is this a rate? Or?) Homework...
  12. Daniel Petka

    B Energy of Gamma Ray Photon with Wavelength h

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  13. Daniel Petka

    B What is the shortest wavelength of all? >0 or h?

    Theoretically of course, what is the shortest wavelength of all? Is it the size of the Planck's constant or just anything over zero?
  14. T

    I Radiation passing through Planck-scale wormholes

    This is something that has really been bugging me lately. There was a study from over twenty years ago that proposed that electromagnetic radiation might have been able to pass from one end of the universe to another in the early universe, furnishing an explanation for the homogeneity of the...
  15. JulienB

    Calculating Planck's integral for finite range of wavelength

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  16. Z

    The Kirchhoff diffraction formula with small wavelength

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  17. W

    E = hf what sort of Energy is this?

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  18. R

    Finding wavelength and fundamental frequency with string

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  19. Theudius

    B Wavelength, Path Difference, Phase Difference

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  20. Samama Fahim

    Spectral Intensity as a Function of Wavelength in Blackbody Radiation

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  21. Daniel Petka

    B Wavelength of Particles Moving at 1m/s

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  22. J

    Wavelength and Frequency in a Waveguide

    The problem states that the wavelength and frequency in a waveguide are related by: ##\lambda = \frac{c}{\sqrt{f^2 - f_0^2}}## then asks to express the group velocity ##v_g## in terms of c and the phase velocity ##v_p = \lambda f## Solution: Given that ##\omega = 2\pi f##, ## \omega(k) =...
  23. L

    A 3rd method of finding wavelength in a double slit

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  24. L

    A laser emitting light with a wavelength of 560 nm (Single slit).

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  25. Cocoleia

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  26. jwkhjang

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    I'm currently studying wavelength and frequency and I've learned about the equation v= f*Lambda. What will happen if temperature is changed? I know that speed of the sound will increase. Does it mean that wavelength will also increase? I was curious because if temp. increases, the frequency...
  27. Buzz Bloom

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  28. G

    I De Broglie wavelength in non-constant potential?

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  29. T

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  30. huffy

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  31. ReidMerrill

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  32. R

    B De Broglie Wavelength & Classical EM Wavelength Comparison

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  33. nso09

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  34. A

    Finding order of diffraction given angle and wavelength

    Homework Statement Calculate the grating constant, d, given that theta = 172.01167 degrees, and that lambda = 447.2 nanometers. 2. Homework Equations d = mλ / sinθ where m is an integer that refers to the order of diffraction where λ is the wavelength where d is the spacing between two slits...
  35. adamaero

    Finding wavelength of visible light in a well

    Homework Statement Determine what colors of visible light would be absorbed by electrons in an infinite well, N = 3.1 nm. The effective mass for an electron is one-fifteenth of the standard electron mass. Homework Equations En = n2h2/(8mL2) E = hf f = c/λ The Attempt at a Solution E1 =...
  36. terryds

    Wave Problem (time for a point to move half a wavelength)

    Homework Statement If a wave y(x, t) = (6.0 mm) sin(kx + (600 rad/s)t + θ) travels along a string, how much time does any given point on the string take to move between displacements y=+2.0 mm and y=-2.0 mm? Homework Equations ω=2πf (but it's not necessary in this problem, this problem just...
  37. G

    B Electron Diffraction and the DeBroglie Wavelength

    I've been reading up on electron diffraction for electron microscopy, and I have been trying to understand the proof for the wavelength of an electron in a tunneling electron microscope. The proof I have been trying to emulate begins as follows: It then says that I must account for...
  38. afcsimoes

    B Is there a minimum wavelength for electromagnetic radiation?

    The wavelength is inversely proportional to the foton energy. So, the limit can be stated by the mass of the full universe. But how much near that limit can the light be?
  39. J

    LED Light Wavelengths: What to Know for Photolysis Prevention

    I work in a factory where we package pharmaceuticals. There are quiet a few products that are light sensitive to a certain wavelength. The lights in the older buildings are fluorescent and were have defined wavelength specification. The wavelength determined the color light/filters set in the...
  40. allenlistar

    Calibrate Spectroscope to Find Wavelength

    Homework Statement A student collects diffraction data using a lamp with known emission wavelengths of 425nm, 565nm, 600nm, and 700nm. These lines appeared on her spectroscope at 32mm, 59mm, 63mm, and 69mm(all measured from the same arbitrary 0mm position). With these data she is able to...
  41. moenste

    Wavelength of the sounds at zero degrees

    Homework Statement A source of sound frequency 550 Hz emits waves of wavelength 600 mm in air at 20 °C. What is the velocity of sound in air at this temperature? What would be the wavelength of the sound from this source in air at 0 °C? Answers: 330 m s-1, 579 mm 2. The attempt at a solution...
  42. moenste

    Find the wavelength of the blue line (line spectrum)

    Homework Statement The line spectrum of a certain substance consists of three prominent lines; blue (B), yellow (Y) and red (R). When the spectrum is examined with a diffraction grating having d = 4 * 10-6 m, it is found that the sequence of lines, moving from the centre, is B, Y, R, B, Y, B...
  43. K

    Threshold Wavelength for Photoelectric Effect - 6.476103179e-19J

    Homework Statement The binding energy of an electron to a metal surface is (3.90x10^2) kJ/mol. What is the threshold wavelength (in nm)for the onset of the photoelectric effect? Homework EquationsThe Attempt at a Solution work function= 3.9*10^2 kj/mol=6.476103179*10^-19j I know I have to...
  44. senobim

    Relate wavelength and energy scale

    Homework Statement Light intensity is measured by monochromator and is given by I(\lambda ) = I_{0}\lambda ^{3} How to change it to the energy scale I(h\nu ) = ? Homework Equations Photons energy E = h\nu, E =\frac{hc}{\lambda } The Attempt at a Solution It's kind of strange to relate...
  45. Deebu R

    Calculating Wavelength in a Medium with Different Speed of Sound

    Homework Statement Ultrasonic waves of frequency 3 x 10^5 Hz are passing through a medium where speed I found is 10 times that in air ( speed of sound in air is 300m/s). The wavelength of this wave in the medium will be in the order of? Homework Equations Wavelength = wave speed/...
  46. R

    De Broglie wavelength and energy levels

    Homework Statement In the earliest circular planetary model of the atom the electron and proton orbited a common centre. The electrostatic forces alone provided the force field. However an accelerating charged body will send out electromagnetic waves and the orbiting charges would consequently...
  47. H

    I Energy associated with matter waves of macroscopic objects

    Consider an object of mass 1kg moving with a speed of 1m/s. Theoretically , the de broglie wavelength associated with it is about 3.6x10-37. Now if we calculate the energy associated with this wave it comes out to be 3x1011. This is a huge amount of energy which could be very hazardous but it is...
  48. Drakkith

    I Wavelength of a Stationary Particle

    We were going over the basics of the photoelectric effect today in my solid state chemistry class when my instructor gave us a question asking what the wavelength of an ejected electron was. We worked through the question and got the answer, but that got me thinking. If the wavelength is...
  49. Thejas15101998

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  50. Sophrosyne

    I Wavelength of photons exchanged between charged particles

    When two electrons approach each other, there is a repulsion between them by the exchange of a photon as the electromagnetic force carrier. Is there a general range of wavelength of such photons? Does it depend on how rapidly these electrons are approaching each other?
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