General College Physics

Wisconsin Lutheran High School

Week 35 (Apr. 20 - 24)

Reading: Interference of light waves (Chap. 37)

Key Topics: electromagnetic waves, intensity, interference, and polarization

Lab: Measuring the width of human hair using laser light interference. When analyzing interference pattern images, you can determine the distance of the center of each interference maximum (bright spot) from the center of the central bright spot. Using these measurements (along with the distance from the hair to the white screen) you can determine the angle, theta, of each bright spot. In your lab report, you must include at least a plot for your own hair. The plot should have n on the x-axis and sin(theta_n) on the y-axis. Is the data linear? If so, how do you determine the hair width from the slope? Hint: young's two-slit interference maxima occur whenever sin(theta) = n * lambda / d, where d is the spacing of the slits.

Week 35 Homework Problems:

Thin film interference problem: Thin film interference: A thin film of gasoline floats on a puddle of water. Sunlight falls almost perpendicularly on the puddle and reflects into your eyes. Although sunlight is white (it contains all colors), the film has a yellow hue since destructive interference eliminates the colors of blue (469 nm in vacuum) from the reflected light. If the refractive index for light in gasoline and water are 1.40 and 1.33, respectively, then determine the minimum non-zero thickness of the film. What if the gasoline was on glass (n = 1.52) instead of water? (answer for part 1: 168 nm)

General College Physics

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Course syllabus

General College Physics is a year-long introductory college-level course for advanced (typically junior or senior level) students at Wisconsin Lutheran High School. It is a dual-credit course offered at Wisconsin Lutheran High School in collaboration with Wisconsin Lutheran College. This means that students enrolled in the course have the option of receiving credit for a four-credit algebra-based laboratory science course from the College.

During the first semester, we will primarily study the science of motion and its relationship to forces. Topics include: dimensional analysis, measurement, uncertainty, estimation, 2 dimensional kinematics, projectile motion, newton’s laws of motion, force diagrams, centripetal force, circular motion, conservation of energy and momentum, torque, angular momentum, oscillations, and gravity. During the second semester, we will explore a number of inter-related topics including: heat, thermometry, the laws of thermodynamics, electricity, magnetism, optics, electromagnetic induction, radiation, atomic theory, and nuclear physics.

Emphasis on theoretical topics, careful thinking, laboratory experiments, and problem solving makes this course challenging. My aim is to help you succeed in this course, and to have fun while learning physics. So please do not hesitate to contact me with any problems you may run into this semester!

Course textbook: The course will be organized around a book: the Pocket Guide to accompany Physics for Scientists and Engineers (4th edition) by Serway. (I’ll call this PSE for short.) I would highly recommend obtaining a copy of this book. It is inexpensive, compact, and well-written. It will make a very handy addition to your home science library. If you don't want to buy it, I will have copies to loan out for the semester.

Course time and location: The course meets on a rotating schedule in WLHS 223—the science wing on the first floor of WLHS.

Professor: Dr. Kuehn from Wisconsin Lutheran College (WLC) is the professor for this course. Contact info: kerry.kuehn[at]wlhs.org

Registration for College Credit: Wisconsin Lutheran College is requiring students in this course who are interested in obtaining college credit. Please apply in the application link below for each class you are wishing to apply for college credit. This must be approved by Friday, September 27.

https://admissions.wlc.edu/register/foundations

Once students apply we will wait for Wisconsin Lutheran College to confirm eligibility and requirements for college credit and communicate out further information. Please reach out to Mr. Davis if you have any questions.

Teaching Assistant contact info: The Thursday course sections (beginning in September) will be overseen by a teaching assistant. Richard "Ricky" Hill is a third-year physics major at Wisconsin Lutheran College.

Course websites: In addition to the course information provided through WLHS’s OnCampus system, we will be also using a website I’ve designed for this course: www.greatphysics.com/WLHS/

Homework exercises: I will assign weekly homework problems. These are designed to deepen your understanding of lecture material and to prepare you for the quizzes and tests. Although I do not intend to regularly grade your homework solutions, I will occasionally do “spot checks” to make sure that you are keeping up with the material. Typically, I will give you credit for submitting in your best attempt by the due date (typically Sunday late afternoon). Late assignments will receive reduced credit.

Laboratory exercises: Some of our weekly assignments will include laboratory work. Labs will typically take up at least two class periods. Your laboratory notebook pages must be submitted by the assigned due date. More details about the required format and expectations will be discussed before the first laboratory period. You will need to order/purchase a dedicated laboratory notebook. Here are guildlines on what to include in your laboratory notebook.

Quizzes: We will have in-class quizzes almost every week on Monday. To prepare for quizzes, you should read the assigned book chapter (at least once), review the lecture material, complete all of the homework problems, and review the homework solutions.

Tests: We will have a midterm exam before the end of the third quarter and a comprehensive final examination before the end of the fourth quarter.

Software: Logger Pro 3.15 Is an excellent data analysis software package. Download for Wndows 10, 8.1, 7, and for macOS 10.14, 10.13, 10.12, 10.11, 10.10. For more details on how to download and install Logger Pro click here.