Specular reflection of light is characterized by a definite relationship between the positions of the incident and reflected rays. The light may be emitted by the object, or may have been reflected by it. Furthermore when the lawn mower moves over the pavement and hits the grass at an angle one of the lawnmowers front wheel will hit the grass and slow down for a. Properties of light upload free download as powerpoint presentation. At least part of the oncoming wave disturbance remains in the same medium.
This means that if parallel light rays are directed at the surface, the reflected rays will consist of parallel rays as well. Use features like bookmarks, note taking and highlighting while reading light the physics of the photon series in. Light may perform reflection, refraction and other phenomenon. When the reflected light reaches our eyes, we can see the objects. The ray model of light has no hope of accounting for that. Reflection, abrupt change in the direction of propagation of a wave that strikes the boundary between different mediums. Specular and diffuse reflection 2 geometric optics.
Jul 17, 2012 light is the common name for electromagnetic radiation with wavelengths of 400750 nm. A ray of light is the straight line along which the light traveled and a bundle of light rays is called a beam of light. Corpuscular theory of light physics and radioelectronics. The lawnmower moving over the grass is analogous to light moving through a medium, such as glass and the lawn mower moving over pavement is analogous to light moving through vacuum. This expectation turns out to be quite wrong instead of a continuous patch of light there is a pattern of light and dark stripes, called interference fringes. Reflection and refraction equipment acrylic block set, planeconcaveconvex universal mirror, cork board, cork board stand, pins, flashlight, protractor, ruler, mirror worksheet, rectangular block worksheet, equilateral prism worksheet, converging lens worksheet. We identify three design principles for reflection and metaprogramming facilities in object oriented programming languages. Foundational level mathematicsgeneral science credential. Reflection occurs when a light ray bounces off an illuminates them.
Its dual behavior is partly explained by 1doubleslit experiment of thomas young who represents the photons motion as a wave and also by 2the photoelectric effect in which the photon is considered as a particle. Often no attempt is made to connect these models, and to provide a unified. And yet, we find that while light travels in a medium, unobstructed by any obstacles, it will travel in a straight line, called a ray. To simplify the diagram a single ray of light is shown as opposed to wave fronts of light.
Choose from 500 different sets of test light reflection physics flashcards on quizlet. Some of it bounces off, some of it goes through, and the rest of it is absorbed. As shown below, an electromagnetic wave is a transverse wave consisting of mutually perpendicular oscillating electric and magnetic fields. Reflection of light class 10 science lec no 1 what. Reflection is an api which is used to examine or modify the behaviour of methods, classes, interfaces at runtime.
A spherical mirror whose reflecting surface is curved outwards, is called a convex mirror. Since it travels at the speed of light, c 3 108 m s. In the process the character of the light may be changed. Specular reflection refers to a clear and sharp reflection, like the ones you get in a mirror. We can say that light propagates as a wave and is emitted and absorbed as a particle. We tackle math, science, computer programming, history, art history, economics, and more. Light waves can interfere with other light waves, canceling or amplifying them. Aug 06, 2017 reflection of light 10 class lec no 1science physics what is reflection. Reflection of light is the change in direction of light rays that strike the boundary between different mediums. Reflection of light and other forms of electromagnetic radiation occurs when the waves encounter a surface or other boundary that does not absorb the energy of the radiation and bounces the waves away from the surface. Light light was considered as mysterious thing in olden days.
This term is sometimes expanded to include ultraviolet and infrared radiation. What is the maximum angle of refraction when a ray of light is refracted from glass into air. However, if the surface is smooth, we see a regular reflection, like a mirror. From the early waveparticle arguments to the mathematical theory of electromagnetism to einsteins work on the quantization of light, different descriptions of what constitutes light have existed for over 300 years. A ray of light is incident normally on a glass slab. When light travels from one medium to another like air to glass, or glass to water, it does three things. Two colors of light that, when combined, produces white light. Light, reflection, and color characteristics of light light is an electromagnetic wave. Somehow light must also carry information about the location and shape of the objects that we see. The first theory of light was put forward by newton.
In a group of four, students discuss what they have learned about reflection. Light is brightness that comes from an object producing light, called luminous body sun. Light deals with luminous energy, energy which causes the sensation of vision. The corpuscular theory explains the reflection of light in exactly the same way as the reflection of a perfectly elastic ball from a rigid plane. The nature of light uw madison astronomy department. In the image you can see the ray of light entering from the top of the frame, hitting the reflective surface say a mirror and reflecting to the bottom of the frame. Most surfaces are rough, or irregular, which scatters the light in all directions. The second part of the law of reflection states, the incident ray, the normal to the surface and the reflected ray, lie all in the same plane, called the plane of. An interesting consequence of this is that a light ray will change direction when passing from one medium to another. Cause of refraction is change in speed of light while entering a different medium. The basics of reflection, some interesting problems. Thus, when it hits a smooth surface, angle of incidence is always equal to angle of reflection. How much time does the sun take to shift by 10 when viewed from the earth.
Use a protractor to draw the reflected rays from points a, b, and c. Study of reflection of light by a moving mirror springerlink. A mirror is made of glass which is coated with a uniform layer of a highly reflective material such as powder. Dec 06, 2015 on this page you can read or download 11th physics refraction of light chapter 8 pdf in pdf format. Specular regular reflection occurs if the wavelength of the light is longer than the size of the irregularities on the surface. A plane wave has flat wave fronts and rays parallel to each other. The earth takes 24 h to rotate once about its axis. Reflection of light 10th class physics chapter 12 geometrical. We see things because light from a light source reflects off their surface. The condition is that the surface is smooth on the scale of the wavelength of light, so that the light can excite each atom independently, and coherently add up all their contributions. This theory treats light as a particle called corpuscle. The fact is our eyes alone cannot see any object until light helps. The wavelength and the velocity of the light wave remains the same.
An insight into the unusual and unexpected properties of light that are. This reflective surface reflects almost all the light incident on it uniformly. The schematic representation of these mirrors is shown in fig. Aug 29, 2010 light and its nature have caused a lot of ink to flow during these last decades. Light reflection physics electromagnetic radiation. List the physical quantities which remain constant when light travels from one medium to another. Laws of reflection and the phenomenon of light reflection. And yet, we find that while light travels in a medium, unobstructed by any obstacles, it will travel. According to classical theory of reflection of light, light always travels the least action path. However, if the light ray enters another medium perpendicularly to the boundary, there is no deviation of the ray even when there is change in speed of light. What is the distance between the pencils head and its image. Use features like bookmarks, note taking and highlighting while reading light the physics of the photon series in optics and optoelectronics. Physics textbooklight wikibooks, open books for an open world. A comprehensive physical model for light reflection halinria.
When light rays are incident on an opaque polished surface medium, these are returned back in the same medium. You are already familiar with the laws of reflection of light. We will consider light waves as plane waves and will represent them by their rays. Some of the so called white light from the sun bounces off grass to become green light. When light propagates in a transparent material medium, its speed is in general less than the speed in vacuum c. Reflection and refraction of light goals and introduction when a source creates light, it is common that the there is no preferential direction in which the light is emitted. Where do reflected rays or their extensions intersect. Different surfaces reflect light to different extents. The human eye is capable of detecting light, which distinguishes it from other regions of the electromagnetic spectrum despite having shared properties with light, most notably.
Jan 20, 2016 how to use the basic principles of reflection and refraction to understand the behavior of lenses and mirrors. New didactic formulation of the laws of reflection of light scielo. Refraction of light is the change in direction of a light ray when it travels from one medium to another. The reflectivity of a surface material is the fraction of energy of the oncoming wave that is reflected by it. Prism and rainbow formation are the examples of refraction of light. Electromagnetic waves are ultimately produced by an accelerating charge. These are posted in the classroom and discussed together as a class. Reflection of light article about reflection of light by. Since the light ray appears to be broken, the phenomenon is known as refraction. A presentation on introduction to light, its electromagnetic nature, reflection, refraction. This phenomenon of returning of ray of light in the same medium, is called reflection of light. There is not much variation in the angles of reflections.
The incident ray that returns back from the surface is known as the reflected ray as shown in the image given. Learn test light reflection physics with free interactive flashcards. The angle of incidence is equal to the angle of reflection, and the incident ray, the reflected ray and the normal to the mirror at the point of incidence all lie in the same plane. Our math missions guide learners from kindergarten to calculus using stateoftheart, adaptive technology. Light reflection and refraction jsunil tutorial cbse. This is feynmans explanation in qed, i think you just misunderstood it as saying that reflection is assumed he just assumed rescattering, and then shows you. If you dont see any interesting for you, use our search form on bottom v.
We normally assume that a thing is located in the direction where the light comes from. Common examples are reflection of light, as shown in figure 21, as well. The light ray, which strikes a surface, is known as the incident ray. This is caused by the reflection of light rays on the mirror. Light the physics of the photon series in optics and optoelectronics kindle edition by keller, ole.
Light the physics of the photon series in optics and. Students know the angle of reflection of a light beam is equal to the angle of incidence. Students trace patterns with their finger while looking at the reflection in the mirror. This tutorial explores the incident and reflected angles of a single light wave impacting on a smooth. When light falls on a highly polished surface like a mirror most of the light is sent back into the same medium. Interference 56 just be a merging of the two pools already seen, bright in the middle and falling off at the edges. Reflection gives us information about the class to which an object belongs and also the methods of that class which can be executed by using the object.
We shall try to understand in this chapter the reflection of light by spherical mirrors and refraction of light and their application in real life situations. Light the physics of the photon examines the photon phenomenon from several perspectives. The first image shows the reflection of light and the second image labels the angle of incidence and angle of reflection. The required classes for reflection are provided under java. Download it once and read it on your kindle device, pc, phones or tablets. Single ray, smooth surface parallel rays, smooth surface rough surface, diffuse reflection r on a smooth surface such as a mirror the incident parallel rays of light reflect parallel and the image formed is. Since the light ray appears to be broken, the phenomenon is. Introduction synchrotron radiation was first observed in 1947 and began to be used as a research tool in the mid1960s. The nature of light as a wave a small disturbance in an electric field creates a small magnetic field, which in turn creates a small electric field, and so on light propagates itself by its bootstraps. When light rays strike the boundary of two media such as air and glass, a part of light is turned back into the same medium. Light enters from air into glass plate which has a refractive index of 1.
1084 1487 690 36 986 1490 1330 45 1487 282 1122 1263 482 1172 236 1393 1579 438 1431 842 1199 961 1017 411 667 685 1437 560 730 945 306 148 1148 686