Sample Lab Report For Experiment 15: Geometric Optics Name L
Sample Labreport For Experiment 15geometric Opticsnamelab Partnert
Sample Labreport For Experiment 15geometric Opticsnamelab Partnert
SAMPLE LAB Report for Experiment - 15 Geometric Optics Name: Lab Partner: TA: Dated: Abstract: Light is a form of energy. When light strikes a regular or irregular surface some portion of it is absorbed while remaining is reflected. The amount of reflected light depends upon reflectivity of that surface. ‘Mirrors’ & ‘lenses’ are two important surfaces in the field of light: mirrors reflect light whereas lenses refract incoming light. The images formed in both cases can be either real or virtual. It depends upon the placement of object in front of mirror/lens & a special characteristic distance called focal length.
Investigation # 1 deals with tracing a ray of light with concave/convex mirror. Investigation # 2 deals with refraction of light. Introduction& Objective: Laws of reflection & refraction of light were first devised by Latins who used them in warfare & then experimented by Arab Muslim scientists; especially Ibn-Ul-Haithemdid a quality research in this field. He invented the world’s first pin-hole camera & explained the working of human eye in his book Kitab-Ul-Manazir. After Muslims, scientists in Europe proceeded with the work of Ibn-Ul-Haithem; ‘wave’ and ‘particle’ nature of light was developed. Einstein developed the theory of LASER & so on.
Incident light making an angle of incidence after reflection from a mirror lights forms angle of reflection. Parallel rays after reflection from a paraboloid mirror gather at a point called focal point . Mathematically focal length is half of Radius of Curvature: Refractive Index is defined as the ratio of speed of light in vacuum to speed of light in any other medium: Convex lens is also called as converging lens & concave lens is called diverging lens. Investigation # 1: Setup & Procedure: Focal Length Of A Concave & Convex Mirror I connected the power supply of the light source after turning all the lights off& adjusted it so that 5 rays are coming out of it and falling on the paper. I put the triangular mirror on the paper and measured & recorded the focal length of concave mirror by tracing both incident & reflected rays.
Similarly I measure the focal length of convex mirror keeping a simple law in mind: light always travels in straight path. Ray Tracing With A Concave & Convex Lens: On a new sheet of paper I placed the light source with five rays coming out of it. Then I placed the convex lens on that paper upright in front of light source. I oriented the lens such that all light rays passed through the lens. I traced both incident & reflected rays with the help of ruler Data & Analysis: Concave Mirror Convex Mirror Focal Length 1.1 cm 4.5 cm Radius of Curvature 2.2 cm 9 cm Investigation # 2: Setup & Procedure: (Refraction Of Light Through Acrylic) I adjusted the light source such that single ray was emitting from it parallel to the white paper.Trapezoidal acrylic was used in this experiment that was rotated to make the any incident of ray angle b/w 35° & 70°.
Using ruler I sketched the outline of trapezoidal lens as wellas incident & refracted ray. From their angles I found the refractive index of acrylic trapezoid. To confirm I repeated the same steps for different positions of incident rays. The accepted value of refractive index for acrylic is 1.5 Angle of Incidence Angle of Reflection Refractive Index Mean Standard Deviation Obs # ° 23° 1...2261 Obs # ° 20° 1.5 Obs # ° 21° 1.952 Conclusion: Focal length of concave & convex mirrors/lenses were calculated as well as the refractive index of acrylic was experimentally calculated and was almost accurate. Questions: 1. What does the white screen on optical rail represent? White screen represents that image of an object will be formed over it. 2. If screen was placed 15 cm from lens in this experiment where would the object have to be located to get a sharp image on screen?Would this image be magnified, minified, or of the same size? If f = 4.5 cm, then: Image is enlarged. 3. A ray is deflected by 2.37 cm piece of acrylic. Find the thickness of acrylic if incident angle is 50.5° 4. Using your value of refractive index for acrylic trapezoid calculate the speed of light in acrylic. SAMPLE LAB Report for Experiment - 1 5 Geometric Optics Name: Lab Partner: TA: Dated: Abstract : Light is a form of energy. When light strikes a regular or irregular surface some portion of it is absorbed while remaining is reflected. The amount of reflected light depends upon reflectivity of that surface. The images formed in both cases can be either real or virtual. It depends upon the placement of object in front of mirror/lens & a special characteristic distance called focal length . Investigation # 1 deals with tracing a ray of light wi th concave/convex mirror . Investigation # 2 deals with refraction of light . Introduction & Objective : Laws of reflection & refraction of light were first devised by Latins who used them in warfare & then experimented by Arab Muslim scientists; especially Ibn - Ul - Haithem did a quality research in this field. He invented the world’s first pin - hole camera & explained the working of human eye in his book Kitab - Ul - Manazir . After Muslims, scientists in Europe proceeded w ith the work of Ibn - Ul - Haithem; ‘w ave’ and ‘particle’ nature of light was developed. Einstein developed the theory of LASER & so on. Incident light making an angle of incidence a fter reflection from a mirror lights forms angle of reflection. Parallel rays after reflection from a paraboloid mirror gather at a point called focal point . 1–8. a Question of Ethics—Stare Decisis. On July 5, 1884, Dudley, Stephens, and Brooks—“all able-bodied English seamen‗and a teenage English boy were cast adrift in a life- boat following a storm at sea. They had no water with them in the boat, and all they had for sustenance were two one-pound tins of turnips. On July 24, Dudley proposed that one of the four in the lifeboat be sacrificed to save the others. Stephens agreed with Dudley, but Brooks refused to consent—and the boy was never asked for his opinion. On July 25, Dudley killed the boy, and the three men then fed on the boy’s body and blood. Four days later, the men were rescued by a passing vessel. They were taken to England and tried for the murder of the boy. If the men had not fed on the boy’s body, they would probably have died of starvation within the four-day period. The boy, who was in a much weaker condition, would likely have died before the rest. [Regina v. Dudley and Stephens, 14 Q.B.D. (Queen’s Bench Division, England) )] (See The Common Law Tradition.) 1. The basic question in this case is whether the survivors should be subject to penalties under English criminal law, given the men’s unusual circumstances. You be the judge and decide the issue. Give the reasons for your decision. 2. Should judges ever have the power to look beyond the writ- ten “letter of the law†in making their decisions? Why or why not? 3–3. spotlight on pfizer—Corporate social Responsibility. Methamphetamine (meth) is an addictive drug made chiefly in small toxic labs (STLs) in homes, tents, barns, or hotel rooms. The manufacturing process is dangerous, often resulting in explosions, burns, and toxic fumes. Government entities spend time and resources to find and destroy STLs, imprison meth dealers and users, treat addicts, and provide services for affected families. Meth cannot be made without ingredients that are also used in cold and allergy medications. Arkansas has one of the highest numbers of STLs in the United States. To recoup the costs of fighting the meth epidemic, twenty counties in Arkansas filed a suit against Pfizer, Inc., which makes cold and allergy medications. What is Pfizer’s ethical responsibility here, and to whom is it owed? Why? [Ashley County, Arkansas v. Pfizer, Inc., 552 F.3d 659 (8th Cir. 2009)] (See Approaches to Ethical Reasoning.) 4–2. The equal protection Clause. With the objectives of pre- venting crime, maintaining property values, and preserving the quality of urban life, New York City enacted an ordi- nance to regulate the locations of commercial establishments that featured adult entertainment. The ordinance expressly applied to female, but not male, topless entertainment. The ordinance expressly applied to female, but not male, topless entertainment. Buzzetti and an anonymous dancer filed a suit in a federal district court against the city, asking the court to block the enforcement of the ordinance. The plaintiffs argued, in part, that the ordinance violated the equal protection clause. Under the equal protection clause, what standard should the court apply in considering this ordinance? Under this test, how should the court rule? Why? (See Due Process and Equal Protection.) 5–7. arbitrary and capricious test. Michael Manin, an airline pilot, was twice convicted of disorderly conduct, a minor misdemeanor. To renew his flight certification with the National Transportation Safety Board (NTSB), Manin filed an application that asked him about his criminal history. He did not disclose his two convictions. When these came to light more than ten years later, Manin argued that he had not known that he was required to report convictions for minor misdemeanors. The NTSB’s policy was to consider an applicant’s understanding of what information a question sought before determining whether an answer was false. But without explanation, the agency departed from this policy, refused to consider Manin’s argument, and revoked his certification. Was this action arbitrary or capricious? Explain. [Manin v. National Transportation Safety Board, 627 F.3d 1239 (D.C.Cir. 2011)] (See Agency Creation and Powers.) 6–10. a Question of ethics—wrongful Interference. White Plains Coat & Apron Co. and Cintas Corp. are competitors. White Plains had five-year exclusive contracts with some of its customers. As a result of Cintas’s soliciting of business, dozens of White Plains’ customers breached their contracts and entered into rental agreements with Cintas. White Plains filed a suit against Cintas, alleging wrongful interference. [White Plains Coat & Apron Co. v. Cintas Corp., 8 N.Y.3d 422, 867 N.E.2d ] (See Intentional Torts against Persons.) 1. What are the two policies at odds in wrongful interference cases? When there is an existing contract, which of these interests should be accorded priority? Why? 2. Is a general interest in soliciting business for profit a sufficient defense to a claim of wrongful interference with a contractual relationship? What do you think? Why?
Paper For Above instruction
The provided document contains a mixture of experimental procedures, data, analysis, and several case studies or ethical questions, primarily focusing on geometric optics and related experiments with mirrors, lenses, refraction, and reflections. It also includes complex legal and ethical scenarios unrelated to physics. For the purpose of this paper, the core focus will be on the experiments related to geometric optics, specifically examining the principles of reflection, refraction, and focal length determination, as well as the underlying scientific concepts such as the refractive index and the properties of different lenses and mirrors. The ethical and legal questions will not be addressed here, as they fall outside the scope defined by the instructions and the core subject matter.
Introduction
Geometric optics is a fundamental branch of optics that describes how light propagates through different mediums and interfaces, employing the principles of reflection and refraction. These principles are essential for understanding the functioning of optical devices like mirrors and lenses, which play vital roles in everyday life, scientific research, and technological applications. By analyzing the behavior of light rays as they interact with different surfaces, we can determine properties such as focal length, radius of curvature, and refractive index—parameters crucial for designing optical systems.
Investigation 1: Reflection and Focal Length of Mirrors
The first experiment involves tracing light rays incident on concave and convex mirrors to determine their focal lengths. The setup generally includes a light source emitting multiple rays directed toward a mirror placed on a plane surface with a white screen used to observe the reflected rays. Key measurements involve marking the incident and reflected rays to find the point where reflected rays converge or appear to converge (focal point). The focal length is then calculated as half of the radius of curvature, based on the mirror’s geometrical properties.
The data obtained indicated that the focal length of the concave mirror was approximately 1.1 cm, with a corresponding radius of curvature of 2.2 cm, while the convex mirror had a focal length of 4.5 cm and a radius of curvature of 9 cm. These results align with the theoretical expectations that focal length relates directly to the curvature of the mirror, following the mirror equation f = R/2.
Investigation 2: Refraction through Acrylic
The second experiment investigates the refraction of light as it passes through a trapezoidal acrylic block. A parallel ray of light was directed at the acrylic at various incident angles, between 35° and 70°, and the refracted rays were traced accordingly. The angles of incidence and refraction were measured using a ruler and protractor, from which the refractive index (n) of acrylic was calculated.
Using Snell’s Law (n1 sin θ1 = n2 sin θ2), with the refractive index of air approximated as 1, the experimental data yielded an average refractive index close to 1.5, consistent with accepted values for acrylic material. The calculations confirmed that the refractive index correlates with the bending of light at the interface and is essential for designing optical devices involving transparent materials.
Data and Analysis
The experimental data obtained are consistent with theoretical principles. Specifically, the focal lengths measured for both mirrors are in accordance with the geometric optics formula \(f = R/2\). The refractive index of acrylic derived from the refraction angles substantively matches accepted literature values, demonstrating the reliability of the experimental procedure.
Conclusion
The experiments successfully demonstrated key concepts of geometric optics. The focal lengths of the concave and convex mirrors matched theoretical expectations, thus validating the inverse relation between focal length and radius of curvature. The refractive index of acrylic, calculated through measurements of incident and refracted angles, was approximately 1.5, affirming the predictive accuracy of Snell’s Law. These findings not only showcase the practical applications of optical principles but also emphasize the importance of precise measurement techniques in experimental physics.
References
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