Interference Definition and 999 Threads

While studying the wiki article for Quantum Superposition, I find this sentence: “An example of a physically observable manifestation of superposition is interference peaks from an electron wave in a double-slit experiment.” Can someone explain how interference proves (shows? demonstrates?)...

Hair/wire laser diffraction interference pattern - does it follow single-slit or double-slit? for single-slit interference, the equation nλ = d (y/D), (d is the width of the single-slit, y is the distance between central BRIGHT fringe to the nth DARK fringe, D is the distance from slit to...

Say I place a magnet on a table, and I have a metal in close proximity. Will its magnetic field change due to the presence of this metal, however minute? What if I had another magnet or the table itself is made of materials the magnet is slightly attracted to? Does this phenomenon even exist?

andrewkirk submitted a new PF Insights post Acoustic 'beats' from mismatched musical frequencies Continue reading the Original PF Insights Post.

Homework Statement Two loudspeakers, A and B, are driven by the same amplifier and emit sinusoidal waves in phase. Speaker B is L = 2.00 m to the right of speaker A. The frequency of the sound waves produced by the loudspeakers is f = 206 Hz. Consider point P between the speakers and along the...

I have a question about 'beats' between two sound waves of slightly different frequencies. Basically, I think I understand everything on this page (and have read a few textbooks on this): http://www.animations.physics.unsw.edu.au/jw/beats.htm . And in practice, I work with this concept all the...

If two photons traveling in the same direction but out of phase cancel each other out, what happens to the energy and momentum?

Although microwaves are not refracted much in the atmosphere, there is some, and the atmosphere does vary a lot, and the GPS depends on a pretty exact timing of the signals between ground to satellite. So how do GPS systems take the atmospheric refraction into consideration?

Homework Statement You have a device that can measure sound waves only if the frequency of the wave is in the range ##0.8 kHz- 20 kHz##. You have a whistle that produces sound waves at ##21.5kHz##. You ride a bike moving away from a wall, at the same time you blow the whistle and hold the...

The beats frequency heard from the interference of two sound waves with frequencies ##f_1## and ##f_2## is $$\nu=|f_1-f_2|$$ Nevertheless the frequency of the resulting wave is not ##\nu## but the mean value of the two frequencies $$f_{resulting}=\frac{f_1+f_2}{2}$$ As far as I understood...

Homework Statement Would you see the same thin film interference pattern in a film of soap surrounded by air and a film of soap on glass? Why or why not? Homework Equations None The Attempt at a Solution Yes, you would see the same thin film interference pattern in a film of soap surrounded...

Homework Statement A double slit apparatus is held 1.2 m from a screen. (a) When red light (λ = 600 nm) is sent through the double slit, the interference pattern on the screen shows a distance of 12.5 cm between the first and tenth dark fringes. What is the separation of the slits? (b) What...

Homework Statement Green light is shone onto two soap films. An observer looking down at the soap films sees that soap film X appears uniformly green while soap film Y has green and black bands. If air is the medium on either side of the soap film, the best explanation of this pattern is...

If we can slightly skew the optics in a HOM setup, so that the phase difference between Beam-1 and Beam-2 varies slowly across one of the detection planes, then would we see dark and bright regions in the cumulative pattern (assuming an array type i.e. spatially resolved detector) ??

Hello, I have downloaded CAD models of a rack and pinion, and I don't seem to be able to mount them up in PTC Creo without quite obvious interference. The pinion has a pitch diameter of 24 mm, and a modulus 2. The "pitch diameter" of the rack is exactly one modulus lower than the tip of the...

I have some newbie kind of confusion The model in question is taken from wikipedia: and If, in the first model, the light ray is reflected back to its source, could there be some kind of detectable interference at the midpoint (where the blue arrows are)? If the answer is yes, would this...

Homework Statement What do interference and diffraction have in common? We are learning the sound waves, but I would like to know all the things they have in common. Homework Equations x2-x1=λ/2 (contructive) 3. The Attempt at a Solution The waves have the same frequency, after the process...

Homework Statement Which waves can have a constructive interference? Homework Equations ∆x=kλ The Attempt at a Solution I think that waves with the same frequency and phase can have a constructive interference. What if they only have the same frequency? Can they create constructive interference?

The superposition of a gaussian beam and a plane wave generates a pattern of rings whose phase shift before and after the focal plane (of the gaussian beam) is ##\pi##. This means that if you measure interference before and after you'll see the minimums and maximums of intensity invert. We can...

Homework Statement Consider a given monochromatic component of sunlight. The electric field drives a given air molecule. Each oscillating charge of the air molecule radiates waves in all directions, some of which travel to the eye of a given observer. But, for a given molecule (call it No.1)...

Hello. I'm interested in the experimental details of the above and have found what I believe to be the original published write up of the experiment. The document is in German and I have managed to get a reasonable understanding of the details mainly from the diagrams and graphs. Translation is...

Homework Statement Light of wavelength λ = 535 nm shines through two narrow slits which are 670 μm apart. What is the maximum number of interference maxima which could conceivably be observed (assuming that diffraction minima do not extinguish them and the screen is arbitrarily large)?Your...

Homework Statement The centres of two slits of width a are a distance d apart. If the fourth minimum of the interference pattern occurs at the location of the first minimum of the diffraction pattern for light, the ratio a/d is equal to: ANS: 1/4 Homework Equations Here are the various...

How exactly does RNAi help in fighting against cancer gene ?

First of all i will post a picture of it ... you can find it ... somewhere sorry this is my first post :I I photographed our television with the flash on in order to recreate a strange patter i saw when looking at the suns reflection in the screen.(with my eyes it's not just the camera) You can...

Hi. The Poynting vector is a 3-tuple of real or complex numbers (depending on the respective formulation of electrodynamics) times a unit. It may be pictured as an arrow with some length and direction in IR^3 or IC^3. But is it a "vector" in the strict mathematical sense, i.e. an element of a...

For the sake of simplicity let's suppose I'm talking about the diffraction of light through one slit. Are the distances between any two consecutive fringes (apart from the central maximum) exactly equal? Assuming the wavelength, slit width, and distance between slit and screen do not change...

Homework Statement White light (most intense at 550nm wevelength) shines on a layer of water (n=1.33) setting on a sheet of plastic film (n=1.25). What minimum thickness of water will produce destructive interference on the surface?[/B]Homework Equations a) phase reversal of light reflecting...

Homework Statement The number of GPS units/receivers on smartphones has increased tremendously. Is this going to cause interference? Why? Homework Equations None The Attempt at a Solution I'm not sure if the units only interfere when they are close to each other or what prevents them from...

Homework Statement Two loudspeakers, A and B are driven by the same amplifier and emit sinusoidal waves in phase. The frequency of the waves emitted by each speaker is 694 hz. You are standing between the speakers, along the line connecting them and are at a point of constructive interference...

Homework Statement In a double-slit interference experiment the slit separation is 8.40 x 10-6 m and the slits are 2.80 m from the screen. Each slit has a width of 1.20 x 10-6 m. 2 lights of wavelength 450nm and 600nm are shone on the same slits. If both of the above light sources are shined...

I would like to get an, if possible, detailed analysis of the phenomenon by which you hear a noise in your radio speakers when the home lights are switched off. It probably has to do with a wave packet emitted due to switching off the lights, which is picked up by the antenna of a conventional...

I understand that fermions are subject to the Schrödinger equation, but photons are not. I understand that interference patterns of electrons are governed by the Schrödinger equation, but with photons it is different. If I understand correctly, then what is the nature of this difference?

Homework Statement In a double slit experiment, the distance between the slits is 0.2mm and the distance to the screen is 150cm. What is the phase difference in degrees, between the waves from the two slits arriving at point P, when the angular distance of P is 10 degrees relative to the...

Homework Statement Light of a wavelength 548nm illuminates two slits separated by 0.25mm. At what angle would one find the phase difference between the waves from two slits to be 2 rads? Homework Equations σ / λ = ΔΦ / 2π σ: path difference λ: wavelength Δφ: phase difference The Attempt at a...

Homework Statement (a) Calculate the minimum thickness of a soap bubble film that results in constructive interference in the reflected light if the film is illuminated with light whose wavelength in free space is λ=600nm. The index of refraction of the soap film is 1.33. (b) What is the film...

If the equation for phase difference, 2(pi)(path difference/wavelength) gave you a value like 12.25pi would that be the phase difference or would it be .25pi?

Homework Statement Consider two sound sources S1 with a frequency of f1 = 3367 Hz and S2 with a frequency of f2 = 3362 Hz. Determine the smallest difference in frequency from 3367 Hz that the average person can detect? Homework Equations The only thing I can think of is approximating the...

I have a confusion regarding interference and diffraction phenomenon, I will be glad if you can post a video or something about interference and diffraction basics. I don't have meaningful concept over their differences. [Mentor's Note: Thread moved to General Physics and thread title edited]

If I understand the delayed choice quantum eraser experiment correctly, it's essentially set up in the manner as the double slit. The only difference is that the detectors are set up in front of the double slits. It was thought that if there was an interference pattern that appeared then that...

Homework Statement In a Young’s two-slit experiment a piece of glass with an index of refraction and a thickness is placed in front of the upper slit. (a) Describe qualitatively what happens to the interference pattern. (b) Derive an expression for the intensity of the light at points on a...

On a single long string, two sinusoidal pulses are started from either end. They have a destructive interference. Both the pulses have kinetic as well as potential energy. Now the point at which they meet, there being a destructive interference, no crest or trough is formed. But right after...

Homework Statement Light of 576 nm wavelength is directed at a two-slit apparatus and produces a famous intensity pattern on a screen 75.0 cm away. Each slit is 0.434 mm wide, and the center-to-center separation of the slits is 0.640 mm. Given that the intensity at the very center of the...

Homework Statement [/B] Consider 2 radio antennas placed on a 2 dimensional grid at points x1 = (300,0) and x2 = (-300, 0). If the antennas are out of phase such that ϕ2-ϕ1 = π/4 and both are emitting waves of frequency 2.59 MHz. What will the amplitude of the resultant wave be at the point...

This post is related to a posting I did a couple of days ago, but I will go into more detail on this one, and it should be more easy to see the concept that is presented. A number of years ago, I was explaining interference concepts to a physics Ph.D. who had very little background in...

Here is a thought experiment which is a modified version of a one I posted 4 years ago. A moving train, where there are two slits at an equal distance from a photon source along the direction of motion open for a short period of time to allow the entry of photons from the source. The source...

How do 2 waves in a double slit get cut? I know that light spreads in all directions so, when a double slit is infront of a light source, then it only allows light that goes through the slit past the wall. Why do interference patterns depend on the wavelength? Isnt the wave length perpendicular...

Hi, When a molecule makes a transition from high energy state to low energy state, it emits electromagnetic radiation with a certain wavelength, which can be collected as emission spectrum. However, I have a question right here: For any real case, there are quite a number of molecules in one...

Take two lasers of the same intensity and wavelength and aim them at 30 degrees at the same spot on a mirror, so that at the surface the waves cancel perfectly. What happens? How can the wave be reflected if there is no field present?

First, I hope this is the correct place for this question. I am experimenting with electrical discharges at low pressure, think plasma globe, and I bought a geiger counter to make sure I am not producing x-rays. My vacuum pump is rated down to 5 pascals. The problem is that the geiger counter...