Physics 4 laboratory snells law, lenses, and optical. The indices of refraction n i and n r are given and the angle of incidence can be measured. The objective of this experiment is to verify the snells law of refraction by tracking a laser ray through a rectangular slab of glass equipment. Lab 9 reflection, refraction and total internal reflection. The law of refraction is also known as snell s law, named for willobrord snell, who discovered the law in 1621. Electromagnetic waves, snell s law we now embark on a fourweek digression to consider the physics of the interaction of light with nonopaque minerals. This law was discovered in 1621 by the dutch astronomer and mathematician willebrord snell also. The second graph verified snells law in the same way. Pdf the present experiment discusses, presumably the most basic method. We get two more equations by applying snells law to the first interface. Refraction and snell s law 1 a fish swims below the surface of the water at point p. Pdf snells law of refraction observed in thermal frontal. Reflection and refraction university of calgary in alberta. Practical physics c phys 2101 by staff of physics 2012.
Review the laws of reflection and refraction and snell s law. A ray is a line that has an origin but does not have an end. Now customize the name of a clipboard to store your clips. Understand the concept of total internal reflection. Notice that snell s law shows that the index of refraction and the sine of the angle of refraction are inversely proportional that is, as the refractive index gets larger n 2 n 1 the sine of the refracted angle gets smaller sin.
Practical investigation aslam khan, keenan wong and jinhyuk yeh 20 aim. Place two more pins, r and s, at the far side of the block in such a position that srpq is a. When light passes from one transparent medium to another the rays of light refract bend. Goals of the experiment to study and observe the laws of reflection and refraction. Refraction and snells law reading shen and kong ch. The slope of the line gives a value for the refractive index of glass. Aim a laser at the glass block so that it emerges on the opposite site. Experiment 6 refraction of light snells law objective. D i have answered all questions asked in the manual during the experiment. In each of these two example problems, the angle of refraction is the variable to be determined. Materials results discussion every angle of refraction was similar slopes represent refractive index taken from octave we think they are all similar because they were all mixed with water if we could redo the experiment we would add more samples to test and try not to dilute. To use snell s law to determine the index of refraction n of a piece of glass and to use it to find the speed of light in that glass materials. A rectangular slab of glass, a laser pointer, a few sheets of paper, a sharp pencil, a ruler, and a protractor.
From te analysis from phase matching from fermats principle of least time total internal reflection and fibers fios. Outline te and tm fields refraction and snells law. Snells law snells law 1 objectives the objectives of. From fermats principle, one can derive a the law of reflection the angle of incidence is equal to the angle of reflection and b the law of refraction snells law. Download snells law experiment engineering document on this page you can read or download snells law experiment engineering in pdf format. Class will have already discussed the basics of waves i. The law of refraction snells law describes the behavior of a ray of light that passes from one medium into another. Nov 27, 2015 on this page you can read or download snell s law experiment memo grade 11 in pdf format. Place a glass block on a sheet of paper and draw its outline. Physics 4 laboratory snells law, lenses, and optical instruments. Theory when light passes from one medium into an optically different medium at an angle other. Experiments in physics physics 1292 general physics ii lab. The objective of this experiment is to use snell s law to determine the index of refraction of a glass plate.
V l2 is the longitudinal wave velocity in material 2. Snell s law equates the ratio of material velocities v 1 and v 2 to the ratio of the sine s of incident and refracted angles, as shown in the following equation. The pdf version of the teacher toolkit on the topic of refraction and snell s law is displayed below. Phet sims are based on extensive education research and engage students through an intuitive, gamelike environment where students learn through exploration and discovery. To verify snells law and find the relationship between angle of incidence and the angle of refraction, for monochromatic light passing from air into perspex. Light traveling through air encounters a second medium which slows the light to 2. Pdf determination of refractive index of optically transparent.
In part 1 of this lab you will investigate the bending of light as it. Application of these principles through the use of a polarizing microscope allows geologists to confirm the hand specimen identification of minerals, to. Snell s law describes the relationship between the angles and the velocities of the waves. Notice that snells law shows that the index of refraction and the sine of the angle of refraction are inversely proportional that is, as the refractive index gets larger n 2 n 1 the sine of the refracted angle gets smaller sin. Snell s law also known as snell descartes law and the law of refraction is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air. The critical angle allowed us to calculate the indexes of refraction. Light is an electromagnetic disturbance and, as such, is described using maxwells equations, which expresses the relationship between the electric. You will be provided with equipment to explore the laws of refraction, how lenses work, and how to use them to make simple instruments. Knowledge and understanding kn kn1 understand the meaning of the terms. Electromagnetic waves, snells law we now embark on a fourweek digression to consider the physics of the interaction of light with nonopaque minerals. The physics classroom grants teachers and other users the right to print this pdf document and to download this pdf document for private use.
To verify snells law and measure the refractive index of a solid diagram apparatus laser glass block protractor procedure 1. The refractive index of glass is equal to the average value of r i sin sin. This document includes several ray tracings which can be used by students to do a takehome lab. This law is more complicated than that for reflection, but an understanding of refraction will be necessary for our future discussion of lenses and their applications. Notes look directly down through the glass or plastic block to measure the angle of refraction. Snells law relates the indices of refraction to the angles of light rays in two media. State the laws of reflection and refraction, describe examples and apply the laws to simple.
This law also applies to the bending of light by lenses and to the guiding of light by the fiber optic cables that carry modern communications signals. With three of the four variables known, substitution into snell s law followed by algebraic manipulation will lead to the answer. With three of the four variables known, substitution into snell s law followed by. The effect that the angle of incidence of white light has on the angle of refraction from one transparent medium to another. Homework statement b a student wants to find the refractive index of a rectangular block of glass. Over time, the clarity of what is now known as snells law has improved, which can be credited to the work of several mathematicians throughout history. This speed is thought to be a universal constant and the highest speed allowed in nature as postulated in. In this experiment you will measure the refraction of light as it passes from one medium to another, and you will determine the index of refraction of a given liquid. Snells law lab report snells law lab christie fosina. He draws around the block and marks the position of a ray of light that travels through the block. It is shown that the sizes of the angles of incidence and refraction are related to the speed of the light through the medium. Hopefully a data table of two sets of angles, incident and refracted, will be generated. Laser level, protractor, plate glass, plain paper, pencil, data sheet procedure.
A straight line through the origin verifies snells law of refraction i. Clipping is a handy way to collect important slides you want to go back to later. Calculate the refractive index for a substance if the speed of light in that medium is. Snell s law of refraction can be derived from fermats principle that light travels paths that minimize the time using simple calculus. This video explains the procedure i want students to follow for doing light refraction measurements. Snell s law is a formula used to discribe the relationship between the angles of incidence and refraction,when referring to light or other waves passing through a boundary between to different isotropic media,such as water,glass and air. Snells law is defined as the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant, for the light of a given colour and for the given pair of media. Physics 11, snells law experiment internet archive. Conclusion the goal of this experiment was to verify snells. Experiment 1 refraction of the light and snell s law objective 1. Kn2 explain refraction in terms of law and index of refraction kn3 understand the behavior of light when it travels between different media kn4 state law. Snells law was used to calculate the angle of refraction. To verify snells law and measure the refractive index of. Fermats principle and the laws of reflection and refraction.
Snell s law also known as snell descartes law and the law of refraction is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media. Physics 4 laboratory snells law, lenses, and optical instruments prelab exercise please read the procedure section and try to understand the physics involved and how the experimental procedure works. Experimental verification of laws of refraction of light. We will be measuring the angles of incidence and refraction and substituting into snell s law to solve for the index of refraction of glass.
Full text of physics 11, snell s law experiment see other formats physics experiment 6 snell s law purpose. An observer at point o sees the fish at 1 a greater depth than it really is 2 the same depth 3 a shallower depth than it really is 2 a fish swims below the surface of the water at point p. Pdf lab 9 reflection, refraction and total internal. The objective of this experiment is to use snells law to determine the index of refraction of a glass plate. We investigate the law of refraction in part 4 of this experiment. V l1 is the longitudinal wave velocity in material 1. A physics 11 experiment on refraction and snell s law. View lab report snell s law lab report from physical s ap physics at carmel high school. Snells law is a general relationship for scattering of waves and has wide applications in optics and acoustics. At the end of the experiment the student should be able to. Adjust the components so a single ray of light passes directly through the center of the ray table degree scale.
Fermats principle states that light travels between two points along the path that requires the least time, as compared to other nearby paths. Snells law, in optics, a relationship between the path taken by a ray of light in crossing the boundary or surface of separation between two contacting substances and the refractive index of each. Snell s law lab christie fosina physics regents purpose. Investigating snells law investigating snells law research question.
Procedure set up the equipment as shown in figure 4. Determination of the refractive index of a glass block. Ppt refraction and snells law powerpoint presentation. In addition, we will be measuring various lengths in order to demonstrate the utility of the sine. The project should include some background information on snell s law, all the steps taken in the experiments, key experimental results and a conclusion about the experiment including identification of the unknown solid from the refractive index. Snells law and then some anthony osinski physics teacher campbell high school prerequisites. Draw the incident and emergent paths of the laser on the paper. Verification of snells law of refraction loreto balbriggan. With the block removed, the student can draw in a normal line and then measure the angle of. Snell s law of refraction can be derived from fermat s principle that light travels paths that minimize the time using simple calculus. If the angles of the incident and refracted rays are. Index of refraction snells law index of refraction dispersion the separation of light into colors arranged according to their frequency, by interaction with a prism or diffraction grating. This explores the relationship between the viscosity of a liquid and the degree of light that it refracts.
Since snell s law only involves sines i wonder whether this minimum problem has a simple geometric solution. Sample problems for snell s law important information snell s law describes how light bends when traveling from one medium to the next. Snells law experiment with glass block physics forums. All trademarks and s on this website are property of their respective owners.
Snell s law holds true for shear waves as well as longitudinal waves and can be written as follows. Mungan, spring 2001 prove the wellknown fact that one gets minimum deviation for a symmetric beam geometry. In 1621, willebrord snell discovered the law of refraction, hence called snells law. Now obtain the ray g by joining the terminal points of rays a and f at. Notes look directly down through the glass or plastic block to. On this page you can read or download snell s law expe riment memo grade 11 in pdf format. Founded in 2002 by nobel laureate carl wieman, the phet interactive simulations project at the university of colorado boulder creates free interactive math and science simulations.
Consider snells law for light inside the lucite block, which strikes an outer surface, surrounded by air. The experiment consists of a laser ray box, laser safety goggles, optics bench, 2 cir cular cartesian. For those interested in seeing a derivation of snell s law, please reference this accompanying lesson. If you dont see any interesting for you, use our search form on bottom v. Problem is that snells law does not just pop out of this data.
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