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Color is a double valued variable.For physics there is a one to one correspondence between frequency of light and the color assigned to visible frequencies. As far as the spectrum of colors (rainbow) ultraviolet frequencies are invisible to our eye. The eye is a biological entity, the retina of the eye has color receptors, and these receptors do see the ...


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There are two different mechanisms at work here. It's not the case that humans are "ultraviolet colorblind" or something like that. 1) There is the spectrum that the flower petal reflects or absorbs. This spectrum is continuous and includes ultraviolet and everything at lower wavelengths, visible light, and infrared and everything at higher wavelengths. 2) ...


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It is an insightful question, and the answer is "Yes". What you describe is often called "frequency mixing", and can be used to generate practically any wavelength we want. Note, however, that to modulate a laser at 100 THz, you need a source to produce a 100THz signal. And, by the way, you seem to be mixing up wavelengths and frequencies. 630 nm (...


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Assuming the electron is being modelled as a wavepacket, then there is no single momentum given by the de Broglie relation. We know this from the Heisenberg uncertainty principle: $$ \Delta x \Delta p\geq\frac{\hbar}{2} $$ Which tells that there is uncertainty in the position and the momentum of the wavepacket as can be seen in the diagram below: Where the ...


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de Broglie's relation relates the momentum of a particle to its wavelength. If the particle's wavefunction contains a superposition of different wavelengths, then the particle's state is a superposition of different momenta, and there will be a fundamental uncertainty in the any measurement of momentum.


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Does this kind of wave have multiple frequencies? For the dispersion relation to be useful (as opposed to just being true) then yes. We find the dispersion relation of a wave by putting in a trial solution of the form $e^{i(kx-\omega t)}$ and then working out the conditions on $\omega = \omega(k)$ for the trial plane-wave waveform to be a solution of the ...


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I think part of the problem is the way you're defining color. As other answers mention, humans generally have three color receptors, which are sensitive to frequency ranges that we call red, green, and blue. Color is what we percieve when those receptors are excited by light, and we percieve a range of intermediate colors when more than one type of ...


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The note produced by vibrating air in the instrument. Blowing air over the player's lips is what sets up the vibration. You can do this without an instrument. The instrument has a resonance frequency. Vibrations at that frequency get reinforced. The oscillating pressure acts on the lips and encourages them to vibrate at the resonance frequency. This makes ...


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Reception and perception Our eyes have receptors (cones and rods), and these are naturally evolved for Sunlight, which is a combination of many wavelengths (containing non visible wavelengths too), and our receptors have evolved so that they are mainly sensitive for visible wavelengths, a tricolor system, red, green and blue wavelength light. Now the ...


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An unaided and healthy (see below) human eye cannot see anything ultraviolet. That's why it is called ultra-violet - in the whole picture of the electromagnetic spectrum it is between the violet visible light and X-rays. What we CAN see related to UV is the tails of mainly-UV spectral features (be they light or absorbtion). That's why we can see the "black ...


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• Why is the UV invisible only sometimes? Ultraviolet Light is always invisible to the human eye, because it lies beyond our visible spectra range . Only UV detectors and specially designed cameras can " See" the UV light. • Does it have to do with the flower using iridescent structures to produce color, instead of a pigment? That is very unlikely , ...


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