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. P

    Exploring Light: Refraction & Wavelength Questions

    Homework Statement 1. What property of light causes the sunlight to reach the Earth before the sun actually appears over the horizon? 2. What is the wavelength, in water, of blue light whose wavelength is 4.5 x 10^2 nm in air? 3.The speed of a certain liquid in a certain liquid is 3/4...
  2. M

    Calculating Wavelength of Radio 4 FM & Explaining Loss in Deep Valleys

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  3. F

    Wavelength / Frequency notation

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  4. V

    So, in a way, they are inverse of each other.

    Homework Statement my question is simple and doesn't really fit the template. Is wavelength and period of a wave not the same thing?
  5. B

    Wien's Displacement Law frequency vs wavelength

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  6. J

    Possible Difference in Light Paths for Coherent Sources at Point P?

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  7. C

    Exploring the Minimum Radius of a Star: De Broglie Wavelength

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  8. C

    De Broglie wavelength of 30keV electron

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  9. K

    Change EM Wavelength: Is There a Substance?

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  10. K

    Why do we use short wavelength photons in Compton scattering?

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  11. K

    Wavelength - distance between a node and adjacent antinode

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  12. R

    Relating Work Function and Wavelength

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  13. D

    How does the wavelength of light affect its intensity?

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  14. S

    What is the wavelength of light in water when it enters a swimming pool?

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  15. K

    Determine the wavelength of the wave

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  16. S

    Problem in the Defination of electon's wavelength

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  17. J

    Refraction index vs. wavelength?

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  18. S

    De Broglie wavelength, velocity of electron

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  19. H

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  20. K

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  21. M

    Blue or Red, Which Wavelength is Absorbed First?

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  22. J

    Wavelength, Frequency, & Speed of Light in Different Media

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  23. P

    Momentum and De Broglie Wavelength in Quantum Mechanics

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  24. Y

    How we can find wavelength of a wavepacket?

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  25. D

    What is the Wavelength of the Scattered Photon in a Collision?

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  26. C

    De broglie wavelength and velocity

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  27. Y

    Relationship between Wave Packet Wavelength & Group Velocity

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  28. T

    Calculating Frequency and Wavelength of Light on Metal Surface

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  29. R

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  30. V

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  31. K

    Wavelength of Light: 0.544µm in Air & Water

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  32. M

    Finding index of refraction using wavelength and 2 angles?

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  33. A

    Wavelength, temperature in transition

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  34. P

    Graphing Wavelength vs Inverse freq. or Period

    According to our lab manual, the graph of Wavelength vs Period : the slope should be the speed of sound. Well, I have a negative slope of -32.2 which is ridiculous, but I can't find out what I'm doing wrong. We had 5 tuning forks , say for instance, 512Hz...the inverse 1/f = 1/512= 0.00195 , I...
  35. G

    Visible Light: Wavelength & Frequency

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  36. R

    What is the wavelength of the incident photon?

    Homework Statement If the maximum energy imparted to an electron in Compton scattering is 45 keV. What is the wavelength of the incident photon? Homework Equations The Attempt at a Solution \lambda_2 - \lambda_1 = h/mc (1 - cos \theta ) My first initial thought was to apply...
  37. G

    De Broglie Wavelength problem

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  38. H

    Wavelength with strange units?

    I'm sorry if this is the wrong forum but in a problem I was given wavelength with the unit as an A with a circle above it, can anyone tell me what this means and how I can get it into more familiar terms (meters, for example)?
  39. H

    Wavelength of scattered wave

    Homework Statement A photon whose energy is 8.00E-15 J is scattered off an electron at a 90 degree angle What is the wavelength of the scattered wave? Homework Equations i know that Lamda = hc/E =6.63E-34 * 3E8 / 8E-15 =2.48E-11m The Attempt at a Solution Does anyone know how...
  40. H

    Be Ion: Calculating Longest Wavelength Absorbed

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  41. Loren Booda

    Longest photon wavelength observed?

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  42. F

    How do you find threshold frequency? (given wavelength and KE of electrons)

    If you are told that a silver surface is irradiated with light having a wavelength of 230 nm that causes electrons to be ejected with 77.67 kJ/mol of kinetic energy, how would you find the threshold frequency? I know that threshold frequency = W / h. W is the work function and h is...
  43. B

    De Broglie wavelength and atom penetration

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  44. R

    Loop Quantum Gravity: Is the Speed of Light a Function of Wavelength?

    Re the article by Bojowald in the October issue of Scientific American about Loop Quantum Gravity. He states that one of the consequences of the theory is that the speed of light is a function of wavelength. Any experimental evidence, or even hint of evidence, that anyone knows of?
  45. B

    Diffraction grating wavelength problem

    Homework Statement Light passes through a 200 line/mm grating and is observed on a 1.0 m wide screen located 1.0 m behind the grating. Three bright fringes are seen on both sides of the central maximum. What are the minimum and maximum possible values of wavelength? Homework Equations...
  46. M

    Reflection of light off film, wavelength and thickness?

    What is the thinnest film of MgF2 (n = 1.39) on glass that produces a strong reflection for light with a wavelength of 680 nm? This is the exact question I am faced with. I didn't really know where to begin so I tried using the ratio of n-air/wavelength to n-film/(new wavelength) to try and...
  47. S

    Optimizing UV Wavelengths for Germicidal Effects in Water

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  48. N

    Why Refractive Index Varies with Wavelength of Light

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  49. S

    Wavelength and amplitude. Are they related?

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  50. S

    Finding the amplitude with frequency and wavelength.

    A wave with a frequency of 190 Hz and a wavelength of 26.2 cm is traveling along a cord. The maximum speed of particles on the cord is the same as the wave speed. speed = wavelength X frequency
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