Reflection Definition and 981 Threads

  1. K

    Total internal reflection zero

    How is that in refraction of light energy is lost but not in case of total internal reflection? Is the loss in total internal reflection exactly zero?
  2. B

    Losses involved in reflection and refraction

    when light is reflected on a surface, there is always going to be some absorbsion by the reflective material. what I'm curious to find out is whether the losses in refraction are compareable? is it just dependant on the transparency of the material?
  3. D

    How Do You Calculate Cylinder Rotation Using Laser Reflection?

    Homework Statement You're helping with an experiment in which a vertical cylinder will rotate about its axis by a very small angle. You need to devise a way to measure this angle. You decide to use what is called an optical lever. You begin by mounting a small mirror on top of the cylinder. A...
  4. P

    Finding a Basis for a Reflection in R^2

    Find a basis Beta in R^2 such that the beta matrix B of the given linear transformation T is diagonal. The Reflection T about the line R^2 spanned by [1 2], [1 2] is suppose to be verticle. B=S^-1AS or B=[[T(v1)]beta [T(v20]beta] so i found the reflection matrix to be...
  5. A

    Reflection of a Wave: Amplitude, Frequency, Velocity

    Homework Statement 1. When a wave is reflected from a mirror, there is no change in its a) Amplitude b) Frequency c) Velocity d) All Homework Equations The Attempt at a Solution I think frequency changes,not sure
  6. M

    Reflection coefficient (osmosis)

    hello ppl, i have a question about the reflection coefficient... since the RC indicates the permeabilty of a membrane for a specific molecule...doesnt that mean (If the RC between 0 and 1) that the concentration of that molecule on both sides of the membrane will become the same after a while...
  7. J

    The process involved in reflection?

    when we have light reflecting off a material, what's going on there? is it something analogous to a gas particle rebounding off a container wall due to Coulomb repulsion? If so, what is it that exerts a force to reverse the photon's momentum perpendicular to the surface it's reflecting off...
  8. A

    Struggling with Total Internal Reflection? Need Help for Exam Prep?

    Homework Statement Hi I wonder if anyone can help. I am having difficulty drawing refracted and total internally reflected rays. I have an exam on Monday. Can anybody recommend good websites that can help? Slight panic. Thanks Homework Equations The Attempt at a Solution
  9. N

    Light Reflection: Does Electric Source Affect Places A, B & C?

    If light is from electric source, would persons on places A, B and C register any light in any spectrum.
  10. M

    Total Internal reflection is Glass Prism Question

    Question about Total Internal Reflection? My textbook says that for total internal reflection to occur 2 conditions need to be met. Light is traveling more slowly in the first medium than the second medium and no.2 is the angle of incidence must be large enough for no refraction to occur. My...
  11. M

    Total Internal Reflection in Glass prism Question?

    Question about Total Internal Reflection? My textbook says that for total internal reflection to occur 2 conditions need to be met. Light is traveling more slowly in the first medium than the second medium and no.2 is the angle of incidence must be large enough for no refraction to occur. My...
  12. V

    Reflection of light through a wine glass with water

    Hello, I came across something interesting on the internet. I saw an image in which a wine glass was half filled with water and put in the middle of the two different colored backgrounds. In the air portion within the glass, the two backgrounds were visible through the glass, however; in the...
  13. A

    Light reflection from edge of universe

    tif we presume that our finite universe has a boundry. This boundry is due to the pull of gravity. Light will slow down and then come back to us. 'i may be absolutely wrong in this'. My question is that the light we see will be from the stars surface that doesn't face us and star moving away...
  14. Z

    Pulleys + Convex Mirror Reflection

    Homework Statement In the given arrangement pulley P1 and P2 are moving with constant speed vo downward and the centre of the pulley P lies on the principal axis of a convex mirror having radius of curvature R. Find the speed of image of pulley P when it is at a distance x from the surface...
  15. H

    Reflection of Waves: Is the Pulse Inverted?

    A pulse reaches the boundary of a medium in which the speed of the pulse becomes higher. Is the reflection of the pulse the same as for the incident pulse or is it inverted? Also, does pulse refer only to mechanical waves and not to electromagnetic waves?
  16. H

    What is the angle of incidence and reflection when facing a plain mirror?

    What is the law of reflection to the object, when it's perpendicular to the reflective surface. For example, if you face a mirror and stare eye to eye with the reflection- what is the angle?If I have understood correctly, the angle of incidence/reflection is equal, so if for the mirror is...
  17. D

    Refraction and Reflection of light

    7. (a) A material having an index of refraction n = 1.30 is used as an antireflective coating on glass with an index of refraction n = 1.50 as shown. (i) What is the phase shift for the reflection at the interface between air and the coating (interface 1)? (ii) What is the phase shift...
  18. E

    Light absorption and reflection

    Hi there! I have a question about the classical interaction of light with matter according the Drude-Lorentz model. Let's suppose that the light in matter has a wave-number k which in general is complex. Then the real part of k accounts for the propagation of light, while the imaginary part of...
  19. L

    Transmission, reflection, and absorbtion

    In order for us to see something, the light photon needs to be reflected, not absorbed or transmitted? Then is it that the same frequency of visible light keeps falling on something, an apple is always red in white light, why does it reflect red?
  20. D

    Lambert's Cosine Law, Computing Diffuse Reflection

    Lambert's Cosine Law, Computing Diffuse Reflection : I have 2 coordinates (5, 6, 0) the light source and (2.3, 1.92, 0) the plane. The diffuse coefficient is 0.6 and the light source intensity is 200. So using the Lambert's Cosine Law, I need to take 0.6 * 200 * the dot product of the...
  21. S

    Total internal reflection mirror?

    Hi all, From what I understand, total internal reflection reflect 100% of light. Suppose you had a transparent material with a critical angle of 45 degrees. Now say you had a cone with a 45 degree angle, and you shined monochromatic light in through the base. Would 100% be reflected (minus...
  22. I

    Find Basis of R^n for Diagonal B Matrix of Reflection T in R^3

    Homework Statement Find a basis B of R^n such that the B matrix B of the given linear transformation T is diagonal. Reflection T about the plane x_1 - 2x_2 + 2x_3 = 0 in R^3. The Attempt at a Solution I just don't even know where to begin. I don't know how to interpret problem or how to...
  23. A

    Heat absorption, reflection, and radiation

    Homework Statement 1.if you were to paint a house that reflects heat during summer and radiates heat during winter nights. which color should a house be painted? green, red, black, white, or pink? 2. why do gardeners mix soot in the soil? The Attempt at a Solution 1.i say it is...
  24. F

    Diffuse Reflection: How is it Computed?

    I'm confused as to how the diffuse reflection is computed as : \frac{1} {\pi} * LightRadiance * cos(\theta) Where cos(\theta) is the angle between the light and the surface normal, and accounts for the light projected onto the surface When considering light reflecting at a point from some...
  25. O

    Monochromatic light and reflection

    http://www.screencast.com/users/trinhn812/folders/Jing/media/07c73e88-45a9-4703-91e1-237b20135d2c I'm not sure why the answer is A. I tried reasoning myself that it has to do with the critical angle, but I can't seem to convince myself.
  26. C

    Light, photons, reflection and percentages

    Hey all, I am new to these forums. I am thinking of taking a distance learning degree in the near future from Open University in Physics, so decided to do some reading up first as it has been a while since I hav etuched physics. Anyway I am reading a book at the minute "Quantam Theory cannot...
  27. D

    Multiple Shock reflection problem

    Here's the problem : Air flows in a passage with an initial Mach No. 2. Determine maximum turning angle A for which 3 regular reflections (i.e. no Mach reflection) of the original oblique shock are possible? Now, what exactly is a mach reflection? Also, what is the minimum Mach number...
  28. A

    What is the cause of reflection?

    what causes the reflection of light from a surface?? why can't light simply move through the shiny surface that reflects it...ya difference in penetrating strength... if we try to explain it at the microscopic level... why would the particles of the shiny surface make it bounce back making an...
  29. A

    How does polarization take place by reflection?

    i wonder how it's possible that due to reflection from water say of light only perpendicular components remain and others are refracted.
  30. P

    Diffused Sun/Moon Reflection: Why Water Appears as Columns

    How would the reflected light from the sun or moon apear if the water surface were perfectly smooth?and why does reflected light from the sun or moon appear as a column in the body of water like here http://www.free-slideshow.com/screens/waves_sunsets/sun-over-the-ocean.jpg
  31. P

    How do free electrons in metals interact with and reflect photons?

    How do free electrons of metals reflect photons? I had read that they first absorb and then emit the photon but if they are free (not bound to an atom and thus not fixed to any old energy level) why should they lose their energy on the first place? Surely they don't have to drop to their...
  32. A

    Why do we measure the angle of incidence or reflection

    Why do we measure the angle of incidence or reflection (or say refraction even) w.r.t normal to the surface and why not w.r.t the horizontal surface?
  33. 8

    Analyzing Reflection from an Absorbing Medium

    Homework Statement 3. Consider the reflection from the boundary between air and an absorbing medium. We can use the usual Fresnel Equations, but with a complex refractive index for the absorbing material. For various angles of incidence, use the real parts of the refractive index to...
  34. T

    Phenomena of reflection of light

    I wonder why is there a gap at the starting of the reflected light when i conduct this experiment? Can anybody explain this to me? Thanks!
  35. D

    Understanding Wave Reflection and Phase Shifts

    I've attached the multiple choice question. The first time round that I did it, I simply just did a phase shift of the whole graph by pi. Basically I just translated the whole graph by pi, resulting in option (D). However, it later came to my attention that by continuing to draw the...
  36. S

    What is the relationship between the reflection angles in a prism?

    Homework Statement For a beam of light shone on a prism, the reflected beams will give twice the angle of the prism. Homework Equations We know that the angle between the incident ray and the normal = angle between reflected ray and normal The Attempt at a Solution i tried drawing...
  37. M

    Polarized Light Reflection: Solving for Intensity

    [b]1. A person riding in a boat observes that the sunlight reflected by the water is polarized parallel to the surface of the water. The person is wearing polarized sunglasses with the polarization axis vertical. If the wearer leans at an angle of 17.0 degrees to the vertical, what fraction...
  38. H_man

    So confused about reflection from metal surfaces

    :bugeye:Hi All... I am really confused about the mechanism of loss of energy when an EM wave hits a metal surface. I always thought the reflection was due to the motion of the electrons in the metal (due to the electric field of the wave). Which suggests that resistive losses would come...
  39. M

    Plane Reflection: Finding the Reflected Vector in a Geometric Plane

    Okay so in a problem I have a vector reflecting off a mirror. I have the equation for the normal of the mirror at the coordinates where the vector of light hits the mirror. The normal of the mirror and the vector incident are in the same geometric plane. How do I find the refection of the vector...
  40. V

    General Formula For Reflection Direction

    An Example Scenario: A particle moves at 32° and collides with a wall. This wall is rectangular in nature, which means that there is both horizontal and vertical sides. On a horizontal tangent, it would work like this (sorry for ugly, not-to-scale diagrams)...
  41. R

    What is the reflection coefficient on a transmission line at a resistor halfway?

    Homework Statement If I have a coaxial transmission line, with a resistor halfway through, and another resistor at the end, how do I calculate the reflection coefficient for the spot where the resistor is halfway? Here is a diagram of what I mean. Dashes and dots are are the lines, and }...
  42. J

    Why do some materials reflect and others absorb light?

    If the question was that why are some materials opaque and why some are transparent, the answer would be found in the energy bands. If energy bands allow such transitions for electrons, that they can absorb photon, then they will absorb it, and the photon does not go through the material. If...
  43. A

    Why can wire mesh reflect radio waves for telescope dishes?

    I’ve heard that the reason radio telescope dishes can be made out of wire mesh is because, so long as the size of the holes is less than (I believe) 1/10 the wavelength of the radio wave, the wave be reflected (it will see the dish as being solid). I was wondering what the physical reason was...
  44. Jadaav

    Understanding Refraction and Reflection for Beginners

    Hey guys, I need some notes on refraction please I don't know anything on it. Also I need to how to get ( draw ) the image of an object behind a mirror step by step please. That would really help me guys.
  45. H

    Change of phase in total internal reflection

    I would like to know if there is change of phase during total internal reflection. (In particular I would like to know if I can cover copper with several microns of glass and have it reflect 200 MHz EM waves coming from water (epsilon(H2O)=80, epsilon(glass)=4)).
  46. S

    Fresnel Equations - Equal Entry/Exit Reflection

    My first (successful) post, hope this isn't silly/trivial. Also hope this is the appropriate area for optics-related questions. While debugging some code that applies the Fresnel equations to transmission of light through multiple layers of planar media, I encountered an interesting feature...
  47. C

    How Is a Point Reflected Across a Plane in Vector Form?

    Suppose you have the plane given by \bold n \cdot (\bold r-\bold r_0)=0 where \bold n is the normal vector to the plane which passes through the point \bold r_0. What is the reflection x' of a point x across this plane?
  48. C

    Refraction and total internal reflection

    A mixture of red and violet light is incident on a glass-air interface. The indices of refraction for red and violet light in glass are n(red)=1.52 and n(violet)=1.538. What color of light enters the air? http://www.webassign.net/cj8/q_10.gif attempt to solve: I found that the critical angle...
  49. M

    What is the reason for phase change of light on reflection from a denser medium?

    What is the explanation for the phase change of pie that occurs when a light ray gets reflected from an optically denser medium? This fact was demonstrated by the Llyod's mirror experiment, but what is the theoretical explanation for it? Thanks
  50. B

    Light Speed and Voyager Space Probes: A Reflection

    I just want to make sure I understand this clearly. Light travels at 186 000 miles/second right? So if something was 10 light years away would that mean that it would take 10 years going at the speed of light to get there? Wouldnt it be possible to make a probe go even half that speed? I don't...
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