Since we will be discussing traveling wave solutions of Maxwell's equations representing light, I strongly encourage you to review Chapter 20 of the Knight book on "Traveling Waves" so are comfortable with basic concepts like wave number, wave speed, and expressions of the form Asin(kx - ωt + φ).
Since we will be discussing traveling wave solutions of Maxwell's equations representing light, I strongly encourage you to review Chapter 20 of the Knight book on "Traveling Waves" so are comfortable with basic concepts like wave number, wave speed, and expressions of the form Asin(kx - ωt + φ).
Note: we will be referring several times to the Einstein's theory of special relativity. If you have not see any special relativity before, you may need to do some supplementary reading in Chapter 36 of the Knight 3e book.
This chapter uses complex numbers to study AC circuits at just the right level for the next few lectures so is the better resource to rely on for this part of the course.
You may also look enjoy browsing through the Purcell-Morin book on your own. This third edition has many worked examples that are a bit more challenging than the Knight book and so just right for the 162 course, and the book is used in some honors intro physics courses at places like Harvard, Cornell, and MIT. We will refer to this book one more time when we discuss the connection of special relativity to electricity and magnetism. Note: there is an electronic second edition of this book available online through the Duke library. While useful for reading about AC circuits, the second edition lacks the many worked out problems that coauthor David Morin added to the third edition.
Also, please finish Problem 7 of Assignment 10, the "Bootcamp on Complex Numbers" before Friday so that you will be ready to appreciate our discussion using complex numbers to analyze AC circuits.
Do not be put off by the length of the assignment, much of it is a guided tutorial on complex numbers that involves many short steps that will take you little time to solve.
It is important that you get up to speed with complex numbers as fast as possible so please do Problem 7 of Assignment 10 (the "Bootcamp" on complex numbers) as soon as possible, preferably by this Friday's lecture.
You will need to rely more heavily on my lecture notes as we discuss Chapter 35 on "AC Circuits" since we will be deviating substantially from the Knight book by using complex numbers rather than phasors to carry out the various calculations. The two approaches are similar (phasors are a less technical way to describe what one is doing using complex numbers) and give the same results, but working with complex numbers will prepare you better for the Modern Physics course and for other physics and engineering courses, and I hope will prove interesting to you in its own right.
This webpage is a simple example of how to create a demo of magnetohydrodnamic propulsion. If this intrigues you, Derek in the demo room can help you get the parts to make one, or even a real engine for a small toy boat that can drive around in salt water.
If you have questions related to the quiz, please ask them during Monday's or Wednesday's lectures or post a question on Piazza.
More generally, you can download lecture notes and lecture slides from the Lecture Files directory.
To access these files, go to the Sakai 162 website and click on the "Resources" link in the vertical column on the left side of the webpage. You will see a folder "Knight quick check files" that contains the .ppt files. You will also see a folder "Knight instructor guides" which contains Knight's suggestions to instructors using his book about what kinds of difficulties students might face when learning this material. I make these available to you in the possibility that they help you identify concepts or issues to concentrate on.
The exam will cover everything in the course so far including material of Chapter 31 and Assignment 7. Since a two-hour exam can not possibly cover all the material, you should focus on reviewing key concepts and ideas as summarized in each Knight chapter, and especially as emphasized in the quiz and homework problems. The questions on the exam will require
The 10:20 am class on Wednesday morning, March 6, will be an optional help session rather than a lecture (but Monday and Friday of next week will be lectures as we start our discussion of magnetic fields). Come to class if you have any last minute questions about course material.
Also look at Section 15.5 of Knight 3e, compare continuity equation for a fluid (associated with mass conservation) with equation for conservation of electron current ie, in each case you have relation v A = constant, where v is the fluid speed or drift speed, and A is a cross-sectional area of some tube.
A good way to prepare for Wednesday's and Friday's lectures is to try to answer the conceptual questions at the end of Chapter 27. We will begin Chapter 28 towards the end of Friday's lecture.
As you read the text, please follow the recommendations of the course syllabus by reading actively: take notes, work out example problems in detail (before looking at the solution), and try to make time to think about whether what you are reading makes sense.
I have also arranged for biophysics, physics, and biology majors to meet with Prof. Austin informally from 4-4:45pm in Room 298 of Physics this Monday afternoon. This is a great chance for you to ask all kinds of questions about Prof. Austin's research or about advice he might have for you about what courses to take or research to try.