Interference Definition and 999 Threads

Homework Statement What is the thinnest film of a coating with n = 1.43 on glass (n=1.52) for which destructive interference of the red component (660 nm) of an incident white light beam in air can take place by reflection? Homework Equations 2t = m*lambda? The Attempt at a...

Two perfectly coherent laser beams point at two different positions on a screen. The energy transmitted by each of the beams is dissipated at the screen - it's either reflected (and thus visible to an observer) or becomes a potential energy of some sort. Now both beams are pointed at a single...

1. The problem statement: A wavelength (λ)550 nm light ray traveling thru a viscous medium n1= 1.46 strikes a a crystal n3=1.5 protected by a film n2=1.25. [b]2. Relevant equation: How can I determine the min thickness of the antireflective coating used to minimize the reflection of...

Homework Statement Radio waves of wavelength 250 meters from a star reach a radio telescope by two separate paths. One is a direct path to the receiver which is situated on the edge of a cliff by the ocean. The second is by reflection off the water. The first minimum of destructive...

Homework Statement Two loudspeakers placed X meters apart are driven in phase by an audio oscillator, whose frequency range is 1300 Hz to 1800 Hz. A point P is located A meters from one loudspeaker and B meters from the other. The speed of sound is 344 m/s. What is the frequency produced by...

I'm doing a lab report on diffraction and interference. I've done several diffraction experiments (single slit, double slit, diffraction grating, Fresnel Biprism) to find the wavelength of the laser used. with Fresnel Biprism, wouldn't the refraction within the prism cause a change in...

"In this study, it is shown with reasons that superposition principle does not work in vacuum. This case can be observed by Young type double slit experiment to be carried out. Since field-field interaction is carried through charged particles, in the absence of charged particles linear...

Homework Statement Finding exact distances / angles for some maximum constructive / destructive interference 'bands' for a two-source interference - fixed source-source distance, d - screen parallel with source-source line segment - screen fixed distance away from sources, L - wavelength...

Homework Statement Two point sources of sound waves of identical wavelength lambda and amplitude are separated by distance D = 2.0lambda. The sources are in phase. (a) How many points of maximum signal (constructive interference) lie along a large circle around the sources? (b) How many points...

erm anyone knows why for destructive interference to occur for a fraunhofer's diffraction pattern, the equation is a/2sin(theta) = m(lamda)/2 , ==> sin(theta) = m(lamda)/a ? where a = slit width lamda = wavelength theta = angle the ray makes with the central axis the problem i have...

Homework Statement 3 waves are represented by these 3 waves inteferring: cos(Θ-π), cos(Θ+π), 3cos(Θ)? cos(\theta-\pi), cos(\theta+\pi), 3cos(\theta). If I want to diagram these, does the cos(\theta-\pi) and cos(\theta+\pi), cancel each other out? Do I need to convert them to sine...

1) In a double-slit experiment, two parallel slits are illuminated first by light of wavelength 460nm, and then by light of unknown wavelength. The third-order (m = 3) dark fringe resulting from the known wavelength of light falls in the same place on the screen as the second-order (m = 2)...

Hi, If I have two different light modes focused onto a single spot, could they interfere? Thanks

why do we see 2waves when we consider interference ?why not three or four?eg when we find out conditions formaxima we look for condition when 2 waves interefere...why not 3?

Homework Statement To waves with the same frequency interfere. The intensity of the two waves are I1 and I2. Show that the resultant intensity is: I = I1 +I2 + 2*sqrt(I1*I2)*cos(δ) Where δ is the phase difference between the two waves. Hint: Use the relation between intensity and...

Homework Statement A two-point source operates at a frequency of 1.0 Hz to produce an interference pattern in a ripple tank. The sources are 2.5 cm apart and the wavelength of the waves is 1.2 cm. Calculate the angles at which the nodal lines in the pattern are far from the sources...

A two-point source operates at a frequency of 1.0 Hz to produce an interference pattern in a ripple tank. The sources are 2.5 cm apart and the wavelength of the waves is 1.2 cm. Calculate the angles at which the nodal lines in the pattern are far from the sources. (Assume the angles are...

If gravitational waves formed interference patterns, or just simply interfere as normal waves, couldn't that result in gravitational anomalies in absence of mass? Destructive interference could be thought of as negative gravity(dark energy), leading to expansive "forces", whilst constructive...

Okay, this may not be more related to soung engineers. But say for example, if there was a concert - an there was a crowd. What formulas and calculations are involved to make sure the the interference of sound is kept to a minimum? As they wouldn't like to have the crowd on the left to have...

Homework Statement Two sound waves, from different sources with the same frequency, 540 Hz, travel in the same direction at 330m/s. The sources are in phase. What is the phase difference of the waves at a point that is 4.40 m from one source and 4.00 from the other. Homework Equations...

Homework Statement In a double-slit interference experiment, the slits are illuminated with a red laser light at 632 nm. The interference pattern seen on the screen is drawn below: How would I carefully draw, in the same diagram, the pattern that you would see with a blue laser at 450 nm...

Homework Statement In Fig. 17-35, sound with a 46.4 cm wavelength travels rightward from a source and through a tube that consists of a straight portion and a half-circle. Part of the sound wave travels through the half-circle and then rejoins the rest of the wave, which goes directly through...

Homework Statement A double-slit experiment is performed with light of wavelength 600 nm. The bright interference fringes are spaced 1.8 mm apart on the viewing screen. What will the fringe spacing be if the light is changed to a wavelength of 400 nm? Homework Equations Fringe spacing...

I am reading texts on fundamental physics about diffraction and interference. When comes to diffraction, it takes a single slit as example and using Huygen's principle to explain how the wave transmitt and form the pattern. It sounds like that the pattern is due to interference. One textbook...

Homework Statement What is the minimum thickness of coating which should be placed on a lens in order to minimize reflection of 661 nm light? The index of refraction of the coating material is 1.40 and the index of the glass is 1.65. Hint: You must take into account the 180 degree...

Homework Statement A piece of paper is placed at the end of an air wedge 4 cm long. Interference fringes appear when the light of wavelength 639 nm is reflected from the wedge. A dark fringe occurs at both the vertex of the wedge and at its paper end, and 56 bright fringes appear between...

Single slit interference. ?? Can someone please explain to me about the single slit interference phenomenon? My teacher said that after passing through the slit, it can be modeled that there are two wave source coming form each end of the "wall" which makes the slit. How can this actually...

Homework Statement The figure shows the circular wave fronts emitted by two wave sources. Make a table with rows labeled P, Q, and R and columns labeled r1, r2, \Deltar, and C/D. Fill in the table for points P, Q, and R, giving the distances as multiples of \lambda and indicating, with a...

EQUATIONS USED I have some conceptual questions about constructive/destructive interference based on the equations: ∆x= nλ ∆x= (n+1/2)λ Where n is any integer MY CONFUSION & EXAMPLE I don’t understand why the condition to get constructive interference is ∆x= nλ, and the condition to...

Homework Statement Two coherent sources of radio waves, A and B, are 5.00 meters apart. Each source emits waves with wavelength 6.00 meters. Consider points along the line connecting the two sources. At what distance from source A is there constructive interference between points A and B...

In '99, Markus Arndt published his paper in which single buckyballs (primarily C60 molecules) were fired at a diffraction grating and quantum interference was found. Arndt's experiment used single molecules that had a velocity of roughly 220 meters per second. The molecules traveled roughly 1...

If you have 2 laser beams, A and B, at right angle with each other, that you send towards a beamsplitter (BS), such that you get 2 output beams from the BS, one being the sum of the reflected part of A and transmitted part of B, and the other the transmitted part of A and reflected part of B...

Homework Statement Suppose the interference pattern shown in the figure is produced by monochromatic light passing through two slits, with a separation of 127 µm, and onto a screen 1.14 m away. What is the wavelength? Homework Equations wavelength = (dsin\theta) / m y=Ltan\theta...

Not really a homework problem. Just wanted to know: When light moves from a medium of lower index of refraction to that of a higher index of refraction, the reflected ray suffers a phase change. (Thin film interference) But the other way round, this doesn't happen. This can be shown by...

Homework Statement When they say the first and third bright fringe, do they mean m=1 and m=0..do we count m=0? And likewise for when they say first and third dark fringe, is it m=1.5 and m=3.5? How would we know when to count m=0? Thanks Homework Equations The Attempt at a Solution

SOLVED Homework Statement A two-slit interference set-up with slit separation d =0.30 mm produces interference fringes at a particular set of angles THETAm (where m = 0, 1, 2,) for red light of frequency f = 4.9×10^14 hz. If one wishes to construct an analogous two-slit interference set-up...

interference vs diffraction ?? given a question with two or more slits , how to determine if it is interference or diffraction?

Homework Statement Having two identical waves, knowing how much they're out of phase with each other, how can I know the amplitude of the resulting wave (as a factor of the original amplitude)? Homework Equations The Attempt at a Solution

Homework Statement In a double-slit interference experiment, the wavelength is 579 nm, the slit separation is 0.12 mm, and the screen is 30.0 cm away from the slits. What is the linear distance between adjacent maxima on the screen? [Hint: Assume the small angle approximation is justified and...

I am trying to understand why it is not possible to produce an EM wave through interference that is completely different from the source waves. For example why can't 2 or more EM waves outside the visible spectrum add up to produce light? I haven't had any physics since high school and I don't...

Homework Statement A uniform film of oil (n=1.31) is floating on water. When sunlight in air is incident normally on the film, an observer finds that the reflected light has a maximum at wavelength (lambda) = 450nm and a minimum at wavelength (lambda) = 600nm. What is the thickness of the...

Homework Statement I was just wondering in double-slit interference, when it's a bright fringe, let's say m=2, does that mean that one wave coming from one of the slits is traveling 2 wavelengths longer than than the other wavelength coming from the other slit? How does that work? Thanks...

Homework Statement Two speakers, one directly behind the other and along the x-axis, emit sound waves along the x-axis. The speaker in the back emits sound with a wavelength of .02 m and the speaker in the front emits waves with a wavelength of .05m. If the two speakers are separated by 3 m...

Hi, I am a grade 12 physics student and as our final evaluation I must teach a section of our textbook to the class. The section I received was "Interference of Waves" and I must also create some kind of lab or demonstration for the class. My idea so far is to set up two speakers playing the...

Homework Statement Light falls at normal incidence onto a transparent film on a substrate as shown i. what is the optical path length difference in the case of normal incidence? ii. if nf>no and nf>ns, what is the condition for constructive interference in the case of normal incidence...

When two waves that are 180 degrees out of phase interfere, the energy from both cancels out. Why is it that, for example, a sound wave, which is a form of energy, can disappear when combined with another when the Law of Conservation of Energy states that energy cannot be destroyed? I posed...

Homework Statement In Fig. 17-35, sound with a 15.6 cm wavelength travels rightward from a source and through a tube that consists of a straight portion and a half-circle. Part of the sound wave travels through the half-circle and then rejoins the rest of the wave, which goes directly...

Homework Statement a)Yellow light Lambda= 589nm falls on a double slit. The distance between two slits is d=0.5 mm the width of each slit is a=100 micrometer. A screen showing the interference pattern is located 4 m behind the slits. Homework Equations What is the distance between...

A simplifying assumption in determining the interference pattern from a double-slit experiment is to assume that the screen distance, D, is much larger than the slit separation, d. This allows us to make the approximation that the two optical rays are parallel as they travel to the common...

Hi I'd appreciate help with the following problem: Suppose I have a Bayesian metric for navigating a trellis to detect the maximum likelihood sequence on a channel corrupted by ISI. The usual Viterbi algorithm works on the usual ML (nonstochastic channel) metric. Now, given the expression for...