Physice- diffraction of light?

Question

diffraction of light. how come the light pattern in so funny when light passed through i narrow single slit? white and dark fringe correspond each other? y?

Answer 1

It might help to consider that light (photons) can travel either as particles (like bullets?) or as waves (like dropping a stone in a mill pond) and the two methods stem from separate theories both of which seem true and useful for different experiments. When working with slits you are working with wave theory. Consider water waves (at the ocean?) striking a slit in the sea barrier. The results will be very different depending on whether the waves are massive, similar in size or smaller than the slit. Each wave has a certain amount of energy (and both a crest and a trough). If you add a crest to a trough the energy cancels. If you add two troughs there is minimum energy. And if you add two crests, there is maximum energy. The photons passing through a properly sized slit relative to the lights wave length can cause energy to add up or cancel giving rise to a small series of bright and dark fringes.

Answer 2

Diffraction refers to various phenomena which occur when a wave encounters an obstacle or a slit. In classical physics, the diffraction phenomenon is described as the interference of waves according to the Huygens Fresnel principle. These characteristic behaviors are exhibited when a wave encounters an obstacle or a slit that is comparable in size to its wavelength. Similar effects occur when a light wave travels through a medium with a varying refractive index, or when a sound wave travels through a medium with varying acoustic impedance. Diffraction occurs with all waves, including sound waves, water waves, and electromagnetic waves such as visible light, X-rays and radio waves.

Answer 3

Diffraction is bending of light into the shadow region when light passes through a narrow slit.

Diffraction of light can be explained if light is assumed to be of wave nature.

Waves show diffraction,

Diffraction is due to superposition of secondary wavelets starting from various points on a wave front.

Path differences between various wavelets have different values in different directions resulting in formation of dark and bright fringes

Answer 4

Change in the directions and intensities of light after passing by an obstacle or through an aperture whose size is approximately the same as the wavelength of the light.


Diffraction is the bending of waves around obstacles, or the spreading of waves by passing them through an aperture, or opening. Any type of energy that travels in a wave is capable of diffraction, and the diffraction of sound and light waves produces a number of effects. (Because sound waves are much larger than light waves, however, diffraction of sound is a part of daily life that most people take for granted.) Diffraction of light waves, on the other hand, is much more complicated, and has a number of applications in science and technology, including the use of diffraction gratings in the production of holograms.

Due to the much wider range of areas in which light diffraction has been applied by scientists, diffraction of light and not sound will be the principal topic for the remainder of this essay. We have already seen that wavelength plays a role in diffraction; so, too, does the size of the aperture relative to the wavelength. Hence, most studies of diffraction in light involve very small openings, as, for instance, in the diffraction grating discussed below.

But light does not only diffract when passing through an aperture, such as the concert-hall door in the earlier illustration; it also diffracts around obstacles, as, for instance, the post or pillar mentioned earlier. This can be observed by looking closely at the shadow of a flagpole on a bright morning. At first, it appears that the shadow is "solid," but if one looks closely enough, it becomes clear that, at the edges, there is a blurring from darkness to light. This "gray area" is an example of light diffraction.

Where the aperture or obstruction is large compared to the wave passing through or around it, there is only a little "fuzziness" at the edge, as in the case of the flagpole. When light passes through an aperture, most of the beam goes straight through without disturbance, with only the edges experiencing diffraction. If, however, the size of the aperture is close to that of the wavelength, the diffraction pattern will widen. Sound waves diffract at large angles through an open door, which, as noted, is comparable in size to a sound wave; similarly, when light is passed through extremely narrow openings, its diffraction is more noticeable.

Answer 5

Briefly, no maths: At narrow slits, compatible with the wavelength the light manifests wave characteristics. From the edges of the slits the light propagates accordingly to the principle Huygens-Fresnel and after that the rays interfere between each other.

Answer 6

You have made a mistake.

It is not diffraction but interference

Answer 7

all varieties of waves (no longer merely gentle) demonstrate diffraction. to comprehend why, it relatively is least complicated to look on the occasion of water waves (ripples on the exterior of water). in case you tension a small merchandise to bob up and down in the water, it creates waves that unfolded from the item in a circle. Now concentration your interest on some small spot in the water it relatively is lots faraway from the midsection (like, say, a hundred feet). you will see that, by fact the waves bypass that element, the "wave front" (the "ridge" of the wave) practically varieties a promptly line. in case you element a video digital camera down onto that spot, you will locate that the waves are shifting in one confident course (say, "north"), no longer diverging (lots) in any respect. Now, in case you look at one tiny spot "X" on your video physique, you will see that the water is arising and down, up and down at that element by fact the waves bypass. yet here, this bobbing action does not reason the wave to unfolded in a circle from "X", yet reasons it to circulate in a promptly line. the reason being that all the standards to the left and precise of "X" are arising and down on an identical time, in unison, and the action of all of them at the same time reasons the wave to maintain shifting in one course (north). yet now, attempt putting a "wall" in the water (aligned east to west), with merely a tiny placing out the place the "X" spot is. The bobbing action at "X" nonetheless reasons the wave to propagate for the time of the small placing out. however the bobbing action on the left and precise facets of "X" is blocked by skill of the wall, so as that action is now no longer waiting to make a contribution to the wave. as a result, whilst the wave passes for the time of the hollow it acts as though there is just one spot ("X") the place the wave is originating from. This has an identical result as in case you have been bobbing an merchandise up and down at "X" in in any different case nonetheless water--it relatively is, the waves start to unfolded in a circle everyday on "X". The waves from "X" are no longer to any extent further going merely "north", yet in addition northwest and northeast. this alteration in process the wave front is what diffraction is. Diffraction happens every time a wave encounters a partial barrier so as that various the wave front is blocked. The blocked area of the wave is now no longer waiting to make a contribution to the wave's propagation, and subsequently can no longer help "steer" the wave front in a promptly line. as a result, the wave veers off from its promptly direction.