Slit Definition and 1000 Threads

Homework Statement Light of wavelength 490 nm is incident on a narrow slit. The diffraction pattern is viewed on a screen 3.6 m from the slit. The distance on the screen between the central maximum and the third minimum is 2 cm. What is the width of the slit? Homework Equations The...

Homework Statement Single-slit diffraction can be observed with any type of electromagnetic wave (not just light). Suppose you want to make a diffraction slit whose width is seven times larger than the wavelength for the following cases. How wide would the slit be? (a) A radio wave for...

Homework Statement An interference experiment employs two narrow parallel slits of separation 0.25mm, and monochromatic light of wavelength \lambda = 500 nm. Estimate the minimum distance that the projection screen must be placed behind the slits in order to obtain a far-field interference...

In double slit experiment, what if we put a detector on one slit, instead of both slits. Does the interference pattern appear or not? I think, if superposition principle is true and particles passing through both slits at the same time, measuring one slit will be enough to collapse its wave...

I have a simple question about the double slit experiment for which I couldn't find an answer elsewhere. Lets say that I shoot one million photons from the source while keeping only the first slit open and that I detect N1 photons on the screen behind the slits. If I now shoot one million...

Homework Statement Hi Can anyone help on this. The questions is as follows: In a double slits experiment using red light, a fringe pattern is observed on a screen at a fixed distance from the double slits. How would the finge pattern change if: a) The screen is moved closer to the...

Homework Statement In a Young's double slit-type experiment using light of 600 nm with 0.5 mm between fringes, a thin plate of glass (d = 100 micrometers, n =1.5) is placed over one of the slits. What is the lateral fringe displacement on the screen? 2. The attempt at a solution To be...

A lecturer is demonstrating two-slit interference with sound waves. Two speakers are used, 1.9 m apart. The sound frequency is 1220Hz and the speed of sound is 343 m/s. Students sit facing the speakers in a row of sear 5.4 m away. Along the row of students, what is the spacing between the...

Homework Statement Consider a Fraunhofer diffraction pattern due to two unequal slits. Let a and b be the unequal slit widths and c the distance between their centers. Derive an expression for the intensity of the pattern for and diffraction angle \theta, assuming the arrangement to be...

THIS IS NOT A HOMEWORK QUESTION...been a while since i did these type of question...just want to refresh my memory...before i forget it. i have a few question... 1) in a single slit: if the wave length is large then...does it mean that the scattering is large or small angle? 2) in a...

The where the interference tassles appear on the film at the double slit experiment, made the conclusion that the waveleghth λ of the wave of the red right is λ=(that much). For the blue light, λ=(that much), and so on. But I cannot find the λ=(that much) for the experiment with electrons and...

Monochromatic light with a wavelength of 419 nm passes through a single slit and falls on a screen 88 cm away. If the distance of the first-order dark band is 0.29 cm from the center of the pattern, what is the width of the slit? My knowns are as follows: L= 88 cm (distance from slit to...

A lecturer is demonstrating two-slit interference with sound waves. Two speakers are used, 1.9 m apart. The sound frequency is 1220Hz and the speed of sound is 343 m/s. Students sit facing the speakers in a row of sear 5.4 m away. Along the row of students, what is the spacing between the...

Homework Statement Two slit interference question: A screen is 2.2m from two slits. The distance from point P to point R (the central maximum to the 2nd dark band) is 1.6mm. This is what the pattern looks like (l) means light band... (d) means dark band ......P...R (d) (l) (d) (l) (d)...

Homework Statement Light of wavelength 460nm falls on two slits spaced .3 mm apart. What is the required distance from the slit to a screen if the spacing between the first and second dark fringes is to be 4mm?Homework Equations dsin(theta)=(m+1/2)lambda where d = .3mm y=4mm lambda = 460nm...

If I "create" a stream of photons in the lab or if I spectographically select a stream of photons from a star, I get the same experimental result in a double slit experiment? In other words there is no difference between photons whose point of origin can be deduced to be eons ago vs those...

Hi, I've been reading about an experiment, where photons are fired through a double slit, and they act as if they go through both slits, by interfering with themselves, and creating an interference pattern on a screen behind. Then if a measuring device is used to see which slit the photon...

I'm a novice at this quantum business and was just trying to understand the single slit diffraction experiment and when an electron's position is getting measured in particular. Given my understanding it looks like the electron's position gets measured twice. Once when it is just about to...

Hi PF. I've finished reading Hawking's "The Grand Design", it was a great book. I'm not a taught physicist but I've always been interested in physics, and I study maths at university. My question was relating to the section where Hawking describes the delayed-choice version of the double slit...

Hi, I was reading Hawking's "The Grand Design" and I came up with a question I didn't know the answer to. He describes a variant of the two slit experiment with particles where a faint light is shone on the slits to determine which one each particle goes through. Naturally this destroys the...

(1) In the double slit experiment, if I fire individual electrons at the slits, is there a chance that an electron could interact with one of the atoms making up a slit in such a way as to alter the energy state of one of its shell electrons. i.e. I could imagine there is a probability of...

In the paper "Double-Slit Quantum Eraser" by Walborn, Cunha, Padua, and Monken (see http://grad.physics.sunysb.edu/~amarch/Walborn.pdf and discussion of the paper at http://grad.physics.sunysb.edu/~amarch/ ), a double-slit quantum erasure experiment is performed with a delayed eraser. When the...

Suppose that instead of two slits for the classical experiment, we use three slits. First what pattern would appear? I tried drawing it out, but without a protractor to draw proper curves, it's hugely inaccurate and I'm too lazy right now. Anyway, to the actual meat of the question, I was...

What happens to the distance between fringes as the width of the single slit become larger? Does the distance between fringes increases? What happens to the centre bright fringe? Does it become larger with an increasing single slit width? My hunch is: Increasing the width increases the size of...

Monochromatic light passes through two slits and produces light and dark fringes on a screen. Initially, the light from the two slits is of equal intensity. The light from one slit now had its intensity reduced. The intensity at the other is unchanged. What changes if any will occur in the...

Homework Statement Monochromatic light with wavelength 580nm passes through a single slit 2.60um wide and 2.10m from a screen. Find the distance between the first- and second-order dark fringes on the screen. Homework Equations y=(n*lamda*L)/d The Attempt at a Solution...

Here is a thought experiment to illustrate the problem... Suppose you have a light source capable of emitting single photons on command from a computer. these photons travel through a barrier with two parallel slits and then strike a charge coupled device. The computer records each strike and...

Hi there, When performing the Young's double slit expt, we always pass the light source through a single slit first before the actual double slits. The typical textbook answer for the use of the first slit is to "produce 2 coherent light sources at the 2 slits", or "to ensure a constant phase...

In this experiment wave particle duality is shown. Without observation the wave function is used. With observation the particle function is used. My question is what is the definition of observation? Specifically in the case of an electron gun is the observer a conductive piece of material...

Homework Statement Two slits are separated by 0.320 mm. A beam of 500-nm light strikes the slits, producing an interference pattern. Determine the number of maxima observed in the angular range -30 degrees < theta < 30 degrees. Homework Equations d*sin(theta) = m*(lambda) The...

Hi, When reading about the Double Slit Experiment, often the author will rave about something like 'the photon must pass through both slits at the same time'. I'm struggling a bit with the simple phrasing of this statement, and can't come to terms with two questions I have: Isn't the...

In the two slit experiment there is an interference pattern generated whenever there are no detectors at the slits. This must mean that the wavefunction associated with the particles have not decohered. But the wavefunction must have interacted in some way with the barrier in order to produce...

Homework Statement A laser beam, with a wavelength of 532 nm, is directed exactly perpendicular to a screen having tow narrow slits spaced .15 mm apart. Interference fringes, including a central maximum, are observed on a screen 1.0 m away. The direction of the beam is then slowly rotated...

When the electron double slit interference pattern is destroyed during measurement detection, to determine which slit the electron passed through, the explanation is that the observation is responsible. Given that detection is done with photons that can interact and alter the path of the...

My first post. I'm an interested layman. 1. There was a thread about this a few weeks ago but it didn't have an explanation that I could understand. Suppose my apparatus has a source that is not centered between the slits. Suppose I can measure the travel time for each particle from...

Actually, I'm studying for my entrance exams to college. I think the professor made a mistake. So , the question says : A diffraction pattern of a light beam from a narrow slit and from a thread are : a)Completely identical b)Totally different c)Identical except for the center. He...

Homework Statement Monochromatic light of wavelength 441 nm falls on a narrow slit. on a screen 2.16m away, the distance between the second minimum and the central maximum is 1.62 cm. a) calculate the angle of diffraction thetta of the second minimum. b) find the width of the slit? Rensick...

In the double slit experiment, a beam of electrons forms an interference pattern on a screen after passing through two slits. If you place a detector on one or both of the slits, the electrons do not form an interference pattern. In this video: Physicist Thomas Campbell makes the...

question about the double split experiment. So detectors placed at the slits create the wave function collapse of the photon! why doesn't the actual slit experiment itself create the wave function collapse?

I've been reading some papers about electron double slit experiments, including the one by Jonsson which seems to be the most detailed and well written so far, but I've only been able to find about five papers total. Jonsson was one, then a 1989 single-electron double slit experiment, and a few...

In the double slit experiment, an observer appears to change the behavior of the particle/wave. Would it be possible to use relativistic simultaneity to explain the change in behavior of particles/waves? A potential passing by, and being observed by an observer, causes the potential to become...

I'm still wrestling with the whole uncertainty principal / wave function collapse idea. Obviously a basic building block of QM, I'm having a hard time understanding the real world evidence which supports these QM piles. 1. So from my understanding, the uncertainty principle tells us it is...

In the double slit experiment, under observation, the electron acts like a particle rather than a wave. From my understanding this is because the photon that hits it for observational purposes adds enough energy into the system to affect the electron and make it chose one single path rather than...

Hello, I would like to know if it is possible to rearrange the components of the double slit experiment so that the particle detectors are placed behind the detection screen? The screen would have to have holes to allow the particles to pass to the detectors when they are activated. Those...

How can a photon, or any other particle, interfere with itself? What does the uncertainty principle have to do with it? Why can't a device be used to track particles/waves? Please help with real answers! Thanks!

I understand how Young used the double slit experiment to prove that light travels in a wave but I am confused on the application of the double slit experiment to electrons. I read somewhere that Young used a 200 angstrom thick sheet of silver as a reflection medium for the light. But, what...

The first question is, how does a single particle(say a photon) interfere with itself? Next, how does measuring it interfere with the interfering pattern? Need help on those please! Thanks!

Reading the derivation for the single slit diffraction minima formula from this site, I'm not convinced about its argument. http://www.math.ubc.ca/~cass/courses/m309-03a/m309-projects/krzak/index.html" What I'm having trouble understanding is the explanation of the formula for minima when m>1...

In the double slit experiment the electron can go through either slit. As long as it is not observed there is an interference pattern as the two possibilities superimpose. The common conclusion to this is that the electron goes through both slits. Is there a parallel with the ground state...

Erm, why do you use a single slit initially? - to produce 2 coherent non-identical sources, but I don't understand why you can't just diffract the beam through the double-slits initially, I thought this would produce 2 coherent sources. Thanks in advance... =]