Wavenumber Wavenumber In the physical sciences, the wavenumber (also wave number or repetency) is the spatial frequency of a wave, measured in cycles per unit distance or radians per unit distance. Whereas temporal frequency can be thought of as the number of waves per unit time, wavenumber is the number of waves per unit distance. In multidimensional systems, the wavenumber is the magnitude of the wave vector. The space of wave vectors is called reciprocal space. Wave numbers and wave vectors play an essential role in optics and the physics of wave scattering, such as X-ray diffraction, neutron diffraction, and elementary
Oh Dear! What Can the Matter Be? me a twopenny whistle He'll buy me a threepenny fair He'll buy me a Bunch o' Blue Ribbons To tye up my bonny Brown Hair O saw ye him coming And saw ye him coming O saw ye him coming Hame frae the Newcastle fair </poem> The following are given as the traditional lyrics (being chorus and verse) in Cuddon's and Preston's "A Dictionary of Literary Terms and Literary Theory": <poem> O dear, what can the matter be? Dear, dear, what can the matter be? O dear, what can the matter be? Johnny's so long at the fair. He promised