Questions tagged [wavelength]

The wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the wave's shape repeats, and the inverse of the spatial frequency or wavenumber. Determined by considering the distance between consecutive corresponding points of the same phase, such as crests. Use for wavenumber, wavelength, frequency.

74 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
6
votes
0answers
81 views

How was Fizeau able to measure interference fringes in his experiment of 1851?

I am wondering how Fizeau, in the famous experiment of 1851, was able to measure changes in the interference fringes given that he used Sun light. Sun light consists of all kinds of wave lengths and ...
4
votes
1answer
61 views

Why and how are wave sets (groups) created?

At a coasts wave normally arrive in groups (sets) and we wondered why this is the case. Some internet research did reveal some clues but no convincing answer. I want to know why waves gather in ...
3
votes
0answers
103 views

Optics: finding total power of a system, including wavelength

Specifically I need to create an ABCD matrix given 2 radii of curvatures, the thickness of the lens, type of glass (BK7) and a given wavelength. I will have to figure this out eventually, so help ...
2
votes
0answers
101 views

Percentage increase in wavelength leads to percentage decrease in energy. (Compton effect)

In this question: What percentage increase in wavelength leads to a 75% loss of photon energy in a photon-free electron collision? My understanding of this question is that $0.25\times E_i = E_f$, ...
2
votes
0answers
26 views

What are upper reflectivity bounds of materials

I know that if i take metal-coated fiber i can send light signals to large distance, because signal would reflect inside fiber, lowering attenuation. Just like in optical fiber communication network. ...
2
votes
2answers
58 views

Which metals are suitable to make structures in GHz and THz applications?

In GHz applications, Cu is mainly used to make structures and in THz applications Al or Au is used to make structure. Is there a special reason to use these metals in particular wavelengths?
2
votes
0answers
314 views

Calculating Natural Broadening of Emission Lines

I'm trying to demonstrate the small effect of Natural Broadening as compared to other types of broadening (Doppler, Stark, van der Waals, etc.) and my calculations don't match the accepted values. My ...
2
votes
0answers
1k views

How does a Fresnel rhomb work (half and quarter wave plate)?

How does a Fresnel rhomb work (half and quarter wave plate)? I am aware of birefringence, which creates a phase shift of $\Delta\phi=\dfrac{2\pi\Delta nL}{\lambda_0}$. But this doesn't explain how a ...
1
vote
1answer
33 views

Formation of Red and blue bands in the sky

Today at the time of sunset I saw this The sky is divided into two parts one In red and one in blue which are very distinctive Can anyone tell how? The upper part of the image points towards the ...
1
vote
1answer
30 views

Refractive index and optical fibre question

This is an A level AQA question: A signal is to be transmitted along an optical fibre of length 1200m. The signal consists of square pulses of white light and this is to be transmitted along the ...
1
vote
1answer
120 views

Propagation of wave on a stretched string

I'd like to describe a scenario in which a wave pulse propagates on a string. Consider a long string with one end fixed to a wall and the other held by a person. Suppose the person snaps his hand a ...
1
vote
1answer
350 views

Doppler shift and speed of rotating objects in space

I understand the concept of how we can use the doppler effect to know if an object is spinning, in the sense that the part of the object spinning towards us will exhibit a blueshift, and the part ...
1
vote
3answers
373 views

Will overlapping two different beams of coherent light with different wavelength cause interference?

If I use two different wavelength lasers to transmit light into a single mode optic fiber will they interfere with each other? If so, how much will be that interference.
1
vote
0answers
59 views

Light wavelengths and intensity at 10 m depth in coastal water

I’m planning an experiment in tanks under controlled conditions in which we’ll collect marine animals and observe their behaviours. We want to replicate to the best the light that they receive under ...
1
vote
1answer
85 views

Is there a significant error in using De Broglie's equation for an electron at really high speed?

I was wondering if using the De Broglie equation $ \lambda = \frac{h}{p}$ for object traveling at really high speeds would result in a significant error. For example if an object travelled at $0....
1
vote
0answers
21 views

Acoustic subwavelength reflection

Acoustic Microscopy is usually used for inspection of airgaps in material. I am looking for any source (textbook, paper) that discusses the percentage of reflection of an acoustic wave from an airgap ...
1
vote
0answers
873 views

Single slit diffraction pattern for electrons?

Reading about Young's double slit experiment for electrons, it is stated that the diffraction pattern is observed when both slits are open but not for a single slit (I suppose this is equivalent to ...
1
vote
1answer
87 views

How to take measurements for wavelength in an experimental wave tank?

To anyone familiar to the experimental hydrodynamics field, how does one experimentally measure the wavelength of the waves generated in a plunger type wave tank or any wavetank for that matter. From ...
1
vote
0answers
393 views

Why does wavelength decide the size/diameter of these holes in the microwave door?

I've read here that microwaves are blocked by the holes in a microwave window because the holes on the door are small enough to prevent the microwaves from passing through. However, if wavelength is ...
1
vote
1answer
62 views

When does the observed wave velocity differ from the actual wave velocity in the Doppler effect?

In some explanations to the formulae of the doppler effect, and also in answers to certain questions, the approach taken is to look at the observed velocity. In such approaches, the observed velocity ...
1
vote
0answers
60 views

Is measuring the speed of light using energy and wavelength cyclical?

I would like to measure the speed of light by directly measuring the frequency and wavelength of a light source. In order to determine the wavelength, I wanted to use a diffraction grating and the ...
1
vote
0answers
85 views

What wavelengths of electromagnetic radiation are emitted by the LH2/LOX reaction?

Rocket engines such as the Rocketdyne Rocket System 68 and the Space Shuttle Main Engine use liquid hydrogen and liquid oxygen as propellants. The exhaust from this type of engine is notable in ...
1
vote
0answers
118 views

Finding the exponent of $\lambda$ in Wien's displacement law

I am reading this paper on a short history of the $T^4$ radiation law. In particular, on page 5, By assuming that the wavelength of radiation emitted by a molecule was a function only of its ...
1
vote
0answers
83 views

Heisenberg theory of uncertainty

I was watching a video on YouTube about uncertainty theory of Heisenberg it said that there is a relation between momentum (multiple of mass and speed) and wave length. And the relation is that if ...
1
vote
0answers
501 views

Angular frequency integral to wavelength integral

I have this integral $$ \bar{\omega}^2 = \int\limits_{-\infty}^{\infty}\omega^2|\tilde{F}(j\omega)|^2\frac{d\omega}{2\pi} $$ and I want to convert it to wavelength domain $\lambda $. I know that the ...
1
vote
0answers
901 views

UV absorption decrease with an increase in concentration

I am working on a project measuring the absorbance of a solution which contains surfactant and hard brine. The solution has a constant concentration of surfactant and varying concentration of hard ...
1
vote
0answers
830 views

Variable wavelength LED

Does there exist a type of LED (or other type of light source) that can change it's wavelength depending on the current/voltage it receives on a second wire? If not, would something like this even be ...
1
vote
0answers
103 views

Physical reality of calculated wavelength from the two measurable phenomena slit distance and fringes distance?

I see some difficulties in answering this question (Have we really measured the wavelength of light?) about the measurement of the light's wavelengths with double slit interference. "... we can find ...
1
vote
0answers
46 views

Fresnel equations of reflection applied to microparticles

I wanted to know if the Fresnel equations of reflection, as described here, can be used to calculate the reflectance on the interface of particles which have a diameter near the size of the wavelength ...
1
vote
0answers
57 views

Unusual waves and one of its parameter

I'm messing up with this java app on the web about waves on a string and i'm really curious about something. The java app is the following : http://phet.colorado.edu/sims/wave-on-a-string/...
1
vote
0answers
302 views

Spreading UV light? Fresnel lenses?

I'm making a little UV exposure box and I'm looking for a way to evenly spread out the UV light. I've used Fresnel lenses to do just this in the past, but that was for visible light. But from what I'...
1
vote
0answers
499 views

How do you super impose two or more signals to occupy a fix area of space with the resultant summed wave?

Is it possible to super-impose two or more signals all sent from different directions as a standing wave with the resulting summed wave occupying a fix area of space that is also a complex area? Do ...
1
vote
0answers
100 views

What is the Zero-dispersion wavelength?

There are a decent number of complex mathematical descriptions of the zero-dispersion wavelength online, but I can't seem to find any basic explanations. So to be redundant, what is it?
1
vote
1answer
914 views

Minimum spread of frequency and wavelength in neodymium laser

What is the equation linking the minimum spread in wavelength and frequency of a pulsed laser, in relation to the lasers pulse time and operational wavelength. For example: If a Neodymium laser ...
0
votes
1answer
42 views

Deriving Planck's Constant from Wien's Displacement Law

So I'm reading an introductory book on Quantum Theory (David Park, 3rd ed.) and I am having trouble with the following question: "According to Wien's displacement law, the wavelength $\lambda_m$ at ...
0
votes
0answers
23 views

Can application of force contract wavelength of particles

When I put the de broglie relation for momentum in Newton's law F=dp/dt I saw that in some way F is inversely proportional to wavelength. So if we apply greater force, the shorter the wavelength ...
0
votes
0answers
20 views

Database of Color Emissions

I am reading about the color Green and am wondering if there is a database anywhere listing the atoms/molecules/powders/minerals and their color wavelengths in various forms. Basically I would like a ...
0
votes
1answer
47 views

How do you combine wavelengths of particles in an atom?

As the problem below results in the wavelength of a single electron, how would this combine/interact with other particles? In an atom, for example.
0
votes
3answers
44 views

Energy levels of electrons in an arbitrary element?

Let's say I want to calculate the wavelength of the photon emitted when an electron of an arbitrary element (let's say Carbon) drops from $n=4$ to $n=3$. Correct me if I'm wrong, but I think I would ...
0
votes
0answers
21 views

Laser Detection Paint

Does there exist a paint which if a pulsed laser of ~1500-1600nm was fired at it it would emit visible light or IR Radation (3-5 micron)? I have seen up-converting inks and paints but I can't find ...
0
votes
1answer
35 views

Dimensions of Faraday shielding mesh

Why should the spacings of the wires that constitute a Faraday cage be smaller than the wavelength of the radiation we wish to prevent from penenetrating inside the cage?
0
votes
0answers
25 views

Which device to measure UV lamp wavelength with high precision

Which techniques and devices are able to measure the wavelength/frequency of a UV lamp within the wavelength range of 50nm - 300nm? Is a VUV Optical spectrometer the right device for this?
0
votes
1answer
79 views

How does spot size of a laser depend on wavelength?

Does the spot size of a laser depend on wavelength? We have a laser source that is fed into a spectrometer to set the wavelength we want. No other optics are used after the spectrometer. I was going ...
0
votes
0answers
44 views

Why are bend losses higher at higher wavelengths in fiber optic cables?

I have been researching the effect of wavelength on macro-bend losses for my extended essay (a 4000 word paper on a subject of your choice, high school level) on fiber optic cables. I asked this ...
0
votes
1answer
52 views

What is the difference between Wien's Displacement Law for peak frequency vs peak wavelength?

While doing research for a high school report I came across the fact that WDL actually has two forms, one for peak frequency and one for peak wavelength, and that these two forms are not the same and ...
0
votes
1answer
92 views

How Negative Color Value is accepted in Tristimulus Values for Mixing Colors?

I read a chapter about Trichromatic Theory of Color Mixture (Yao Wang, et all. 2001), about how we can produce most colors by mixing 3 primary colors. And the amount of three primary colors required ...
0
votes
0answers
44 views

Can the em wave pass through matter obstacles and how?

I know about Faraday's cage, and another screens, but I do not understand the physics of this processes. Well, I know that the atoms are almost empty, so there are a lot of free space to em waves to ...
0
votes
2answers
87 views

Does Wave-Particle duality exist at high speed?

I know that relativistic DeBroglie wavelength is given by $λ = h/γmv$. And $γ ≥ 1$, so at higher speed $λ$ will get shorter and shorter, does this mean it will start behaving like a particle and wave ...
0
votes
0answers
124 views

Effect on angular width of central bright fringe

In a single slit experiment when the light of a smaller wavelength is used what happens to the angular width of central bright fringe?
0
votes
1answer
296 views

How to find out the wavelength for the blue led diode?

I need your help as I am stuck and I dont know where to start. I have got four blue leds diode that come with dark blue led lights that I really want to get the same led colours for my 3 fans, but I ...