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Scattering

Scattering is a process where certain forms of radiation are forced to deviate from a straight line by non-uniformities in the medium which it passes. This also includes the difference of the reflected radiation from the angle estimated by the law of reflection.

The scattering theory is used to understand the scattering of waves and particles. Wave scattering corresponds to the collision and scattering of a wave with some material object. For instant, sunlight scatters by rain drops to form a rainbow. Scattering consists of the study of how solutions of partial differential equations, propagating freely “in the distant past”, come together and interact with one another or with a boundary condition; then it propagates away “to the distant future”.

Scattering and Scattering theory is a research field in quantum mechanics. These areas of active research include radar sensing, medical ultrasound, semiconductor wafer inspection, polymerization process monitoring, acoustic tiling, free-space communications and computer generated imagery.

Blob Size

Suppose that you purify a viral DNA sample consisting of double-stranded DNA molecules of length 50,000 basepairs and suspended in salt solution. Using light scattering, you find that each molecule is a blob of diameter about 2 µm. Your lab partner prepares a DNA sample, in the same buffer solution, from some other organism; he

Bragg Scattering of Waves Incident at an Arbitrary Angle

** Please see the attached file for the complete problem description ** Could you please help me with the follow question (the diagram is attached): Bragg's Law applies to a very particular diffraction geometry. Determine the condition for constructive interference for the following, more general, geometric configuration.

Sample Physics Problems

I am preparing for a physics examination. I have attached some past examination questions. Please explain me the solution to the attached questions in detail. Here are some of the questions from the attachment. Please see the attachment for complete and all the questions. 21. A bat approaches an insect of wing span length

Physics: Rutherford scattering; find thickness of wall

A beam of particles strikes a wall containing 2 x 10^29 atoms per m^3. Each atom behaves like a sphere of radius 3 x 10^-15m. Find the thickness of wall that exactly half the particles will penetrate without scattering. What Thickness would be needed to stop all but one particle in 10^6 ? Answer should be: 0.123m and 2.44m

Diffraction in a cubic crystal lattice composed of 2 elements

A compound of two elements crystallizes in crystal structure such that the atoms of type A are located at relative positions in teh conventional cubic unit cell of (0,0,0); (0,1/2,1/2); (1/2,0,1/2) and (1/2,1/2,0), and of type B which are located at (1/4,3/4,3/4); (3/4,1/4,3/4) and (3/4,3/4,1/4). What type of crystal lattice

Wave incident upon a regular lattice of identical atoms

See attached file for more details. 1. A plane wave in incident upon single atom regular lattice. Calculate the scattered amplitude from all the atoms. 2. For the unit cell vectors given, find the value of alpha, beta and gamma where maximal diffraction will be observed. 3. Define the Brillouin zone and demonstrate that

X-Ray Spectrum and mammography

A)Describe the two physical processes that give rise to the production of X radaition when electrons bombard the target of a diagnostic x-ray tube operation at 1000kvp. Explain the shape of the energy spectrum of photons from the target, detailing how this is modified by changes in kVp and target material. (b)Describe how th

Structure Factor and Intensity of Diffraction

See the attached file. BaTiO3 has a primitive cubic lattice and a basis with atoms having fractional coordinates Ba 000, Ti 1/21/21/2, O 1/21/20, 1/201/2, 01/21/2 Show that the X-ray structure factor for the (00l) Bragg reflections is given by F_hkl = f_Ba + (-1)^1f_Ti + [1 + 2x(-1)^1]f0, where f_Ba is the atomi

Ideal gas with vibrational degrees of freedom.

Consider the model of an ideal gas, where every molecule has an additional vibrational degree of freedom, which can be described by an oscillator potential. Since there is no interaction between the molecules (apart from a very weak interaction which allows a thermal equilibrium to arise) the oscillators can be regarded as decou

Particles Scattered from a Beam

A beam of 6 MeV particles scatters from a gold foil of thickness of 0.6 µm. (a) What fraction of the particles is scattered between 1° and 2°? (b) What is the ratio of particles scattered through angles greater than 2° to the number scattered through angles greater than 15°? What is the ratio of particles scattered thr

Atomic Physics

1.) In a Rutherford scattering experiment, an α-particle (charge = +2e) heads directly toward a gold nucleus (charge = +79 e). The -particle had a kinetic energy of 4.9 MeV when very far (r -> ∞ ) from the nucleus. Assuming the gold nucleus to be fixed in space, determine the distance of closest approach. (Hint: Use c

De Broglie Wavelengths

I need some help with this question, look at the attached file for the diagram: A beam of neutrons is moving with a speed of v = 3000 m/s and is diffracted from a crystal of table salt (NaCl), which has an interplanar spacing of d= 0.282 nm. (See figure.) a. Find the de Broglie wavelength of the neutrons. b. Find the angle o

Linear momentum and collisions - white and yellow ball

A white ball is moving and has a speed of 2 m/s and a yellow ball is at rest prior to an elastic glancing collision. After the collision the white ball has a speed of 1.23 m/s. To the nearest tenth of a degree, measured counterclockwise from east, what angle does it scatter at if the yellow ball is scattered at 280 degrees?

Sketch the sixth-order Feynman diagram

Sketch the sixth-order Feynman diagram representing Delbruck scattering: r + r -> r+ r. (This process, the scattering of light by light, has no analog in classical electrodynamics.) This question is from the textbook 'Introduction to elementary particles' by David Griffiths.

Born approximation problem

Demonstrate, for a particle scattering from a finite-range, spherically symmetric potential V(r), which is weak enough so that the Born approximation for symmetric potentials is valid, that the total cross section, at very low energies, is a linear function of the energy σ(E) = σ0(1+αE), where σ0 is related t

A Ring on an Vibrating String

We put a small ring of mass m on the long (infinite) string. The ring slides without friction. How does the ring move, when we send by a string the sine wave? (I need mathematical equation of moving.) How does the wave scatter on the ring? (I need the amplitude of scattering waves, or reflection coefficient R). Please provide

The propagation of Light: Scattering

Multiple choice: 1. Compared to an object in front of it, the image in a plane mirror is always: (a) smaller (b) virtual (c) three times far away (d) distorted (e) none of these. Explain your choice. 2. A chicken is standing 1.0 m in front of a vertical plane mirror. A woman is standing 5.0 m from the mirror, behind and in l

The propagation of Light: Scattering

Question: 1. Modern picture frames sometimes come with "nonreflecting" glass (i.e., glass whose surface has been deliberately made rough). What does it actually accomplish? 2. How is it that you can see your image in the surface of a polished black automobile? Explain what's happening. What allows you to see the gin in a gla