Semester 1 Extra Credit for Unit 1 Test: Ch. 31 Diffraction and Interference The idea that wave fronts from light are made up of tinier wave fronts was originated from the Dutch mathematician and scientist Christian Huygens. Every point acts like a new source of waves from the light. Huygens’ principle states that every point on any wave front can be regarded as a new point source of light. The laws of reflection and refraction can be shown using Huygens’ principle as well. The concept of diffraction occurs when a wave bends in a way other than reflection or refraction. Diffraction occurs to some degree in every shadow. The amount of diffraction depends on the wavelength and the size of the obstruction that casts …show more content…
The experiment used a light of a single color, or monochromatic light, and two closely spaced slits or pinholes. He realized that the bright fringes of light resulted from light waves from both holes arriving crest to crest, creating a constructive interference. He also realized that the dark areas resulted from light waves coming from trough to crest, creating a destructive interference. The interference fringes made were straight lines. This interference experiment demonstrated the wave nature of light idea generated by Huygens 200 years earlier. Interference patterns are not only found as double-slit arrangements, but also as a multitude of closely spaced parallel slits making a diffraction grating. A prism separates the colors of light by refraction while a diffraction grating separates colors by interference. Common diffraction gratings are visible in things like costume jewelry and feathers of …show more content…
This also causes for many different frequencies. The waves of an incoherent light are rampant and out of phase causing them to interfere with one another. On the other hand, a beam of light with the same frequency, phase, and direction is called a coherent light. In this form of light, there is no interference of waves within the beam, and only a beam of coherent light will not spread and diffuse. Coherent light is produced by a laser, or light amplification by stimulated emission of radiation. Many people believe that a laser is a source of energy; however, it is only a converter of energy. Lasers are used in many different fields and can be used in many applications. One of the most impressive versions of the laser is the hologram. A hologram is a three-dimensional version of a photograph produced by the interference patterns of two laser light beams. It contains the whole message or entire picture in every portion of its surface. The two laser beams are actually part of one beam; one part illuminates the object and is reflected from the object to the film and the second part is reflected from a mirror to the film, called the reference beam. It may appear to be an imageless piece of transparent film to a normal person, but its entire surface is made up of a pattern of tiny interference fringes. The diverging
Perhaps many are confused about the existing commands linux, this time I will discuss about the linux basic commands used along with examples of its use. 1: Seeing identification (id and group id number) $ Id 2: Looking the calendar date of the system a. Looking at the current date $ Date b. See calendar $ Cal 9 2002 $ Cal -y 3: Seeing the machine identity $ Hostname
1. Identify the range of senses involved in communication • Sight (visual communication), Touch (tactile communication), Taste, Hearing (auditory communication), Smell (olfactory communication) 2. Identify the limited range of wavelengths and named parts of the electromagnetic spectrum detected by humans and compare this range with those of THREE other named vertebrates and TWO named invertebrates. Figure 1: the electromagnetic spectrum source: www.ces.fau.edu Vertebrates Human Japanese Dace Fish Rattlesnake Zebra Finch Part of electromagnetic spectrum detected ROYGBV (visible light) detected by light sensitive cells in the eye called rods and cones.
The factor involved in this process is called the law of reflection. Because this law has only been applied to rays in the real world, i.e. rays of light, it is defined using rays and mirrors. However, this experiment requires the replacement of the mirror and rays of light, with a shield and target. “The law of reflection states that the incident [shield], the reflected [shield], and the normal to the [target]… lie in the same plane. Furthermore, the angle of reflection is equal to the angle of incidence .
The device would create a phenomenon where a scene from outside the dark room would be projected through the pinhole and on the wall of the dark room. The experiment proved that objects were reflected or entered into the eye, this was known because the projected image would always be reversed and flipped as it entered the pinhole. This experiment also revealed that light travels in straight lines. The Book Of Optics has left a huge legacy behind, influencing many optical studies in the
The machine first receives the high energy electromagnetic wave from the Sun (in this case, its X-ray and UV) and has it colliding with a free electron. Then, the photon transfers some of its energy to the free electron. Therefore, the photo becomes less harmful and since the energy goes into increasing the electron’s kinetic energy which then generates electricity.
This is where he noticed different spectral lines between the light emitted from the candle and the light emitted from the sun. This discovery led to his invention, the spectroscope. This new instrument allowed him to investigate the spectral lines of many light sources. These lines of absorption (the dark lines) became known as Fraunhofer lines. His knowledge on light diffraction of many types of glass was nearly unparalleled and helped him to build some of the most innovative refractive lensing technology of its
This discovery used geometry and science to explain how what type of light the sun puts out at certain times of the day does to objects and their shadows. As someone seeks to discover something beneficial to others, they first research
INTRODUCTION Our project is based on Snell’s Law; we want to see if it is possible to measure the speed of light using inexpensive everyday objects like gelatine or water. Many underprivileged schools lack the equipment to demonstrate different laws to their students this has caused many people to lose interest and not fully understand the importance of science in society as well as the learning material they have been given. If our experiment is viable it will decrease this problem and allow these underprivileged schools students to reach their full potential in their learning material. Snell’s Law states that the ratio of the sines of the angles of incidence and refraction of a wave are constant when it passes between two given media.
The volunteers would then push a button, and hear two sounds, which were split by one second. Accompanying one of the two sounds would be a single photon, to which the volunteers would have to say which one they think they saw a photon and how confident they were with their answer. From their research, it was concluded
It all lead to the invention of the Laser Interferometer Gravitational-Wave Observatory; lovingly referred to as the LIGO. The LIGO is a machine that spans about two and a half miles. It is made of two tubes that are at 90-degree angles and form an “L” shape. At the end of each tube is a mirror.
In a controlled situation such as a lab, in which a team of scientists are trying to discover the relative speed and position of any given particle, HUP is more readily observable, but in a situation such as a speed trap it is barely observable. Seeing as most people can’t get a team of skilled scientists and a particle accelerator on short notice, and the change on a car is nigh unnoticeable, we are left with one really practical experiment to demonstrate HUP’s counter intuitive nature. Taking a laser pointer and a clamp of some kind, capable of being closed completely, HUP can be demonstrated by shining the laser pointer through the slit in the clamp and slowly closing it. At first, it’s just a circle of light, but as it gets closer and closer, the light becomes just a thin line of light. But interestingly enough, as the space between the jaws of the clamp becomes closer to zero, the light will begin to expand again into a vaguely oval shaped spot of light.
The amount of refraction a light wave experiences is expressed by the difference between the angle of refraction and the angle of incidence. The light wave traveling to the boundary at an angle of incidence of 45 degrees for example will refract towards the normal because the medium it is now travelling through ( water, glass, diamond ) is more optically dense than the first medium ( air ). Below is a diagram of a light wave approaching three boundaries at an angle of 45 degrees. The medium is different in each example, causing different amounts of refraction. From the three boundaries above the light wave that refracted the most was the air to diamond boundary.
When closely observed, the light will also change the direction it travels as it passes through the two media (Air to Glass). The transmitted wave/light will experience refraction at the boundary between media. As we observe the diagram on the right, the individual wavefronts will bend as it cross the boundary. Once the wavefront cross the boundary, it travels in a straight line, hence why refraction is known as a boundary behaviour. The diagram shows a ray drawn perpendicular to the wavefronts which represents the direction which light travels.
The pinhole design allowed for the future use of lenses and film by taking the same concept and increasing its efficiency. Alhazen introduced the original design in where the light is transferred through a hole and then displayed onto a recording format such as paper or film. The Light Spectrum
The plano-convex lens is replaced with another glass plate and a section of optical fibre was placed between them at one end. Light falling normally on the plates will be reflected back out with a phase difference. Figure 3: Apparatus set up for finding the thickness of an optical fibre, showing the optical fibre between the two glass plates This is due to the fact that some of the coherent light waves were reflected from the top plate and others from the bottom, this path difference resulted in the interference of these waves with one another. This caused an interference pattern similar to the below image: Figure 4: Image similar to the observed interference pattern.