What is Wavelengths: Definition and 231 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

    Re: CMB Redshift Question (Visible Wavelengths)

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  2. L

    Something that absorbs at longer wavelengths looks more red?

    So the colors we perceive are a result of photons of a certain wavelength being reflected back at us. So why in a recent experiment I did, did nanoparticles which had an absorption band that red shifted as the reaction proceeded, look more and more red from an initial yellow color? If the...
  3. Z

    How to estimate how many wavelengths wide a laser is?

    Homework Statement I've conducted two laser experiments. One with single slit, and one with a double slit. I've produced two graphs which look something like these...
  4. C

    Wavelengths / film / reflected light

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  5. O

    Wavelengths along a Smith Chart

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  6. P

    Index of refraction of different wavelengths

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  7. S

    Tension in a rope, wavelengths, etc. I

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  8. P

    Air vs Water Sound Wavelengths: Calculating at 10°C | Grade 11 Help ASAP

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  9. P

    Calculation of a planet's mass via wavelengths

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  10. B

    Diffraction grating problem involving two wavelengths.

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  11. P

    Doppler Effect (Proving equal wavelengths )

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  12. B

    Wavelengths due to electric dipole transitions

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  13. J

    I just noticed that we tend to call EM wavelengths shorter than

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  14. B

    Help with an equation about waves and wavelengths

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  15. W

    How far away is the rock face? (Wavelengths)

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  16. L

    Does anyone know what the smallest and longest wavelengths of light

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  17. B

    Calculating Speed from Light Wavelengths

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  18. Vorde

    Different Wavelengths of Light in Particle View

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  19. S

    Wavelengths of different colour of light

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  20. E

    Diffraction with two wavelengths?

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  21. L

    Radio wavelengths for carbon monoxide (how to find atomic number

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  22. L

    Multiple wavelengths of light through much larger single slit

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  23. L

    Multiple wavelengths of light through much larger single slit

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  24. K

    Doppler Effect: Wavelengths of Sound Waves

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  25. 6

    Wavelengths of Light: Color Wheel & Measurements

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  26. N

    Wavelengths in nm to frequency

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  27. L

    Why do different objects absorb and reflect different wavelengths of radiation?

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  28. A

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  29. R

    How many wavelengths are there now in one pulse?

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  30. H

    Range of wavelengths from a laser pulse?

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  31. L

    Wavelengths of a laser pulse and inductance in tuning of an FM radio

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  32. L

    Deviation of wavelengths through barium crown pism

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  33. O

    Diffraction grating wavelengths question

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  34. G

    What Wavelengths of Light are Most Effective for Photosynthesis?

    What wavelengths of light can plants grow in? Which do they grow best in? How much does this differ from plant to plant? For example, could you grow a plant under monochromatic light? Infrared light? UV light?
  35. P

    What are the resonant wavelengths?

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  36. D

    De Broglie wavelengths and electron diffraction

    I am interested to know why in any description of electron diffraction apparatus they seem to suggest that the electrons need accelerating up to 5kV (or at least several kV) to show the electron diffraction rings, this seems to give a de Broglie wavelength of around 1.2 x 10^-11m whereas the...
  37. A

    Wave & Wavelength: Exploring Questions & Answers

    Are waves only 'waves' if you try and represent them in 2D? If an object emits waves in all directions are the waves more like expanding spheres? If a wave/sphere hits us and the source is sufficiently far away (and strong?) do we 'experience' it as though being hit by a plane? or multiple...
  38. S

    Angular separation between two wavelengths

    1. using differentiation,find the angular separation in arc minutes in second order for two wavelengths 589.0 and 589.6 nanometers 2. d sin(\theta)=m (\lambda) 3. i try to use D=\delta\theta/\delta\lambda by differentating d sin(\theta)=m (\lambda) i got d/m sec(thetha).this...
  39. Z

    Stargazing Telescope size and wavelengths

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  40. L

    For the different wavelengths of radiation, what do the wave crests correspond to

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  41. B

    Separation of two wavelengths in a diffraction grating.

    Homework Statement Light with two wavelengths (510.0 nm and 525.6 nm) is spread by a diffraction grating. On a screen 4 meters behind the grating we observe that the diffrence between the two second order maximum is 1 cm. What is the grating constant (d) ?Homework Equations I think i only need...
  42. S

    Infared WAvelengths in transition through energy levels

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  43. J

    Wavelengths introduction please

    Homework Statement So, I was wondering how I can correlate frequency, amplitude, wavelength, period, and time with each other. I'm trying to solve this problem. A 4.5 Hz wave with an amplitude of 12 cm and a wavelength of 27 cm travels along a stretched horizontal string. a) how far does a...
  44. N

    Why do black bodies emit light at all wavelengths when heated?

    Why do "black bodies" emit light at all wavelengths when heated? Light emitted from an object is made of photons that are emitted when electrons drop into lower energy states. And there are only certain energy states in an atom that electrons can occupy, so only certain wavelengths (aka...
  45. E

    Find how many wavelengths of a wave are in a section of wire

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  46. B

    Wavelengths in a ripple tank experiment

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  47. M

    Calculating Resonance Wavelengths

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  48. P

    Electromagnetic Spectrum Wavelengths

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  49. E

    Wavelengths increasing with space?

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  50. morrobay

    Y displacements in sine wave at (x) and (x + 2 wavelengths)

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