Wavelength Definition and 1000 Threads

Homework Statement A diffraction grating having 500 lines/mm diffracts visible light at 30°. What is the light's wavelength? d = 1/500(lines/mm) = 2x10-6(m) θ = 30° = pi/6 rad⇔ Homework Equations d*sin(θm) = mλ The Attempt at a Solution when i rearranged the equation, i got λ =...

Homework Statement Hello there, a question that I have been given is to "find the wavelength of light emitted from an electron jumping from the 2nd to the 6th orbital (or vise versa if that matters). The atom is hydrogen" Homework Equations E= \frac{hc}{λ} The Attempt at a Solution...

Homework Statement How much will the wavelength of the incident X-ray photon change by if it is scattered by 30 degrees when it interacts with an electron? Homework Equations This is Compton scattering. This is the equation I used: lambda ' - lambda (0) = (h)/(m(e)c) (1-cos...

Quick question: Finding the wavelength?? Homework Statement The energy of a photon is 5.87 x 10^-20 J. What is its wavelength in nanometers? I use E = H(c/λ) Correct? Since I am trying to find λ, I change it to this? λ = H(c/E) ? 6.63x10^-34 x (3 x 10^8 / 5,87 x 10^-20) =...

If this is the wrong place to be posting this, feel free to lock this thread. I wasn't sure if this belonged in "classical physics" or "quantum physics"; this seemed like the appropriate place, but I'm not 100% certain, as it does involve subatomic particles. Anyways, to get to the matter at...

According to de-broglie's equation λ=h/p, so a/c to this equation what would be wavelength of particle at zero speed?

Homework Statement Hi:redface: Light of 500nm wavelength is reflected from a thin film of air between two glass plates. The thickness of the film is 1000mn. a) How much farther does the light reflected from bottom surface travels than the light reflected from the top of the film...

Hi all, I am in introductory physics and we are doing a self-designed lab. For my lab, I wanted to study the relationship between the wavelength of light and voltage. To do this, measured how much voltage drop there was in a single celled solar panel when I put colored filters over a light that...

While deriving De-Broglie wavelength we equate mc^2 to hf and then for electron we change c to v but as far I know mc^2 is rest energy then how could c be converted into v for electron.Shouldnt it have the same rest energy?

What's the relationship between a wavelength and the difference between consecutive resonant lengths (ΔL) for closed air columns? Basically, what's an equation for λ in terms of Δresonant length? Thanks!

Homework Statement A laser with wavelength d/8 is shining light on a double slit with slit separation 0.300 . This results in an interference pattern on a screen a distance L away from the slits. We wish to shine a second laser, with a different wavelength, through the same slits. What is the...

Homework Statement a) Write down the formula that relates the maximum electron energy, Emax. to the frequency of the incident light in the photoelectric effect. b) Calculate the maximum wavelength of light for which photoemission occurs for light incident on a metal whose workfunction...

While playing around with some laser diodes I have at home ~(405, 550, 650 nm) I have noticed that the refracted angles through some mediums (all?) is different. That is, if I fire my 405nm laser through some water at \theta_{1}=80°, the angle of refraction is ~\theta_{2}=47.01±0.05°. Now...

I'm reviewing for one of my final exam and I can't seem to figure out this problem: Find the Debroglie wavelength of an electron with a KE of 40 ev. I got an answer of 3.9 x 10^-10 m. I keep getting it wrong and I'm not sure what to do. Thanks in advance!

I'm going through the Light & Optics chapter of Kaplan MCAT prep material & am having a hard time conceptually understanding the relationship between index of refraction & wavelength or with frequency. It says in the book that n = c/v, & "when the speed of the light wave varies with...

Is cycle the same as wavelength? Thanks!

Homework Statement Photons of energy 12 eV are incident on a metal. It is found that current flows from the metal until a stopping potential of 8.0 V is applied. If the wavelength of the incident photons is doubled, what is the maximum kinetic energy of the ejected electrons? Homework...

Homework Statement Two flat glass plates are stacked and a thin paper strip is inserted between them at one side, creating a narrow wedge-shaped space between the plates. As shown in the figure below, monochromatic light that has a wavelength in air is directed at the plates from above. When...

Homework Statement Hey guys, So I just did a problem here: (its find wavelength of particle with mass) https://www.physicsforums.com/showthread.php?t=596936 But I need to figure out how to find the wavelength of a Photon with no mass. I know the formula I need is this: wavelength =...

Homework Statement Does the following question ask what my title says? I study pack says "How to find the wavelength of a particle with mass?" So, is the following question good? Question: What is the deBroglie wavelength of an electrion with a speed of 2.2x10^6 m/s Answer I got...

Homework Statement Two sinusoidal waves with equal wavelengths travel along a string in opposite directions at 7.72 m/s. The time between two successive instants when the antinodes are at a maximum height is 0.324 s. What is the wavelength (in m)? Homework Equations vt=x Also...

A proton at room temperature with an energy of 0.025eV has a deBroglie wavelength of about 1A (1E-10 meters). If we shoot two proton beams at each other with is low energy and large wavelength what happens? Do they scatter as if they are small hard particles of size about 1 fermi (1E-15 meters)...

What is the wavelength of the interfering waves? Homework Statement Standing waves are produced in a string by sources at each end with a frequency of 10.0 Hz. The distance between the third node and the sixth node is 54 cm. a) What is the wavelength of the interfering waves? b) What is...

Hi guys, i'd really like to understand physics but for some reason I'm not coping. Not sure if it's the calculations or something. But I'm willing to learn, I'd appreciate some help with this problem:Homework Statement A B string on a guitar with a length of 33cm is held fixed at both ends...

Hi, I'm doing a experiment/report on this topic, I'm trying to get a better understanding of the equation "nλ = dsinθ" ALL length measurements are in meters for simplicity's sake. n = bright spot number from the central bright spot (n0) d = distance between slits The angle "θ" and distance...

Hi I have read a paper, where they distinguish between wavelength and frequency modulation. More specifically: "FMS (frequency modulation spectroscopy) can be broken down into two regimes: wavelength modulation (WM) and frequency modulation (FM). In the case of WM, the modulation depth is...

I've asked this question about 4 times on yahoo but no one seems to have the brains to answer it! Looking at the diagram: Just trying to get a better understand of "λ = asin Ѳ" I've marked what I think is the wavelength...can someone please advise? as I'm trying to get a report done...

Homework Statement A quantum of electromagnetic radiation has an energy of 0.877 keV. What is its wavelength? The speed of light is 2.99792 × 10 8 m/s, and Planck’s constant is 6.62607 × 10−34J · s. Answer in units of nm Homework Equations E=hf v=fλ ... λ=v/(E/h) The Attempt...

de broglie's formulation: λ=h/(mv) the more the momentum of a particle, the less wave-like behaviour it shows. But what if we have electron which is stationary, i.e. zero speed, according to formula λ becomes ∞. What does this mean? Does the electron disappear?

Homework Statement Suppose one photon has a wavelength of 6770 nanometers while a second photon has a wavelength 1/6 as large. What is the ratio of the energy of the second photon divided by the first photon? Homework Equations Not sure. The Attempt at a Solution Don't...

[FONT="Times New Roman"]So I was reading about De Broglie's theory of particle-wave duality the other day and I came across the equation: λ=h/p. I expect most of you are familiar with this equation but if you're not, it is: wavelength = Planck's length over momentum (mass x velocity). So I...

Homework Statement A rhinoceros is calling to her mate using sound wave whose frequency is 5.0 Hz. Her mate is 480 m away. The air is 35°C. How many wavelengths of the sound are between the two animals? Homework Equations v = 331 + (.6)*T v = wavelength*frequency The Attempt at a...

I've searched online and on the forum but still can't find an explanation or mechanism behind why diffraction is dependent upon wavelength. For example, assume a water wave that diffracts around a small boat (smaller than the wavelength). The degree of diffraction decreases as the boat gets...

Homework Statement Hey guys, new to the forums so hopefully you can help. I have been given the frequency (and hence the wavelength) of a microwave of 10GHz, and the conductivity of Al which is 3.53x10^7 Siemens/m. From this I have worked out the skin depth. But it asks also what the...

why does the wavelength of light or sound waves affect the degree of bending?I know the mathematical formula for fringe width,but i want to know the physical reasons behind the phenomenon of bending. Taking the example of light passing through a small slit,the huygens principle talks about...

In diffraction why the slit width has to be the order of wavelength of wave? I don't understand. The smaller the width of the slit i think the more effective diffraction becomes. Why the width has to be order of the wavelength?

how can waves like sound have different wavelengths with same frequency?(Wα1/frequency) For eg, in air vel=wav*freq which in solid is more. So, either frequency or wavelength should change. But, since frequency is source dependent, its only the wavelength that changes. My Doubt is that how...

When light or any other electromagnetic wave enters from one medium to another, there is a change in its speed. Speed of a wave is given as v = frequency x wavelength. My question is, what does change, frequency, wavelength or both? If you say... this change in speed is generally attributed...

This follows some questions/points made in my light and sight thread. I have been trying to work out the relationship/difference between photons and waves. I now think that a photon is a discrete particle like amount of energy needed to jump an electron from one orbit to another, perhaps call...

When looking at say water waves, long wavelength means high energy e.g. a tsunami, and waves in a rough sea - compared say to ripples on a pond. But when looking at photons and electrons and other "matter waves", short wavelength equals high energy. Why is it completely the opposite?

We know that speed of sound in liquid is more than in air. Also, velocity of sound = wavelength X frequency. Now there's a change in speed of sound from air to liquid, so, wavelength or frequency should have got changed... But, generally, frequency won't change for an object (correct me...

This question has gone unanswered by our friends in nuclear/atomic threads. My question relates to a solitary Tc^99m decay in particular, and to gamma rays in general. If light is a collapse able wave function, are different wavelength energies the same, ie gamma, x, radio, etc. My...

Homework Statement An excited atomic state has a lifetime of 1 ms. What is the uncertainty in its energy? The photon emitted during its decay is 550 nm in wavelength. What is the uncertainty and fractional uncertainty in its wavelength? Homework Equations ΔEΔt≥hbar/2 The...

Do different materials (i.e. granite, steel, water, etc.), all at the same temperature, emit the same infrared wavelength?

While reading on Cerenkov radiations I've been coming across statement to this effect: It has been noted that the number of photons at a particular frequency or wavelength, as it turns out, is proportional to 1/l2 How is that (mathematically) so?

I already understand the notion, but what I don't get is how that leap is actually logical. Wouldn't you have to assume the photons and atoms are somehow "attached" to the fabric of space? It seems like the same thing as saying Earth's atmosphere is attached to it's crust.

I read recently that the "number of photons emitted by a charged particle is inversely proportional to wavelength" with regard to Cerenkov radiations. (The wavelength refers to the radiation which is of comparatively shorter wavelength, towards the blue-end.) I was looking for a more detailed...

Homework Statement Hi The FSR of a laser with length L is given by Δv = c/2L. If I want to find what Δv is in wavelength, then how do I do this? Obviously I need c=vλ, from which we know that Δv/v = Δλ/λ. But the last equation I can't apply to this case, since it refers to errors around...

Hi! This might very well be a silly question. In many courses I've been presented as an obvious fact that it won't work to use (e.g.) light with a wavelength larger (at least, not much larger) than the thing you want to resolve. Why is this exactly? Thinking of photons I could find no...

Homework Statement Hi Say I have an energy level centered around λ with some linewidth Δλ, and I wish to find the corresponding frequency linewidth Δν. What I would use is the following relation Δλ/λ = Δν/ν. Is this correct? Thanks in advance. Niles.