PHYS 325 :: Physics Illinois :: University of Illinois at Urbana-Champaign

Course Description

General overview

You should go to the section you are registered in, as space is limited. Attendance at discussions is part of your grade. 

Physics 325 is the first half of the complete classical mechanics sequence (Physics 326 is the second half).  Physics 325 will probably require more work than your previous physics courses and is a serious departure from "the plug-n-chug from the formula sheet" mode of operation to which you may have become accustomed.  You will be deriving analytic expressions, and learning to critique and interpret and apply them.   I expect you to know first year calculus thoroughly and be prepared to go beyond that level.  Topics such as matrices, vector mathematics, multivariable calculus, and differential equations covered in PHYS 225 will be assumed.  Concurrent registration or completion of Math 285 or equivalent is also expected.   If you plan on taking Physics 326, I strongly encourage you to take a linear algebra class (e.g. Math 415) this semester.  Here are links to a couple of collections of math and physics formulas that you may find useful during this course, some of which you may recognize.


Classical mechanics is an old subject, and as such there are many texts. Some that are recommended (and that should be on reserve in Grainger) are

You are not required to buy a book. However, I encourage you to read the text to get a different perspective on the class. Furthermore, reading the indicated sections before class will give you an opportunity to familiarize yourself with the material of the lecture before the lecture is presented. Lectures tend to be much more clear when you have skimmed the material before hand. Lectures will be fairly self contained, so in principle one doesn't need a textbook at all. The lecture notes that I am using as well as a slightly different set of notes used by past instructors are posted on the course website.


Please review the section information for lecture and discussion times this semester.

Discussion problem sessions

When registering for this course, you registered for a problem session, which will take place weekly. Because space is limited, please try to go to the section for which you are registered. You will be able to access the problem session materials through the course schedule page. Discussions happen on Monday, and will be graded for attendance only. Please show up on time.

Please review the section information for problem sessions scheduled this semester.


Homework is an essential part of this course and accounts for 18% of your grade. The homework will be assigned (and made available online) at the end of the each Thursday lecture and will usually cover the lecture material of that day and the following Tuesday.  Solutions will be due one week later, on the following Thursday. You should upload your completed homework to Gradescope; it must be in the virtual box by 3:00 pm on the Thursday that it is due to receive credit. 

I don't object to people working on the homework problems together as long as the work that you hand in for grading is your own. Specifically, do not hand in work that is obviously copied. All work must be your own, with your own reasoning and working. Partial credit will be awarded on homework and exams, so please write out your problems neatly showing all steps and writing IN WORDS what you are doing and your reasoning. This will allow the graders to assign partial credit, and point out where you have made errors. I strongly recommend that you thoroughly struggle with the problems yourself first before you seek out help. You'll learn more this way and you'll do better on the exams when you're on your own. Trust me on this one.

You are free (in fact, encouraged!) to use computer software such as Mathematica, Maple, or Matlab to complete your homework problems. However, do not turn in output from these programs, unless a problem specifically asks for it (i.e. plots or code). You will not have this capability on the final exam, so I suggest that you use these resources wisely and do not rely on them to do simple algebra, or solve simple differential equations.

You will be able to access the homework assignments through the course schedule page.

We are using Gradescope for the online submissions. You will be added to the appropriate space. Please contact me if this has not happened by the time the 1st HW is due.


There will be two (in-class, in usual lecture location at usual lecture time) midterm exams worth 15% each and one final exam worth 40%. For all exams, no calculators or computers will be allowed. Notes will be allowed in the form of a standard 8.5"x11" sheet of paper filled with handwritten notes. For the 2 hour-exams, you are permitted only a single side, for the final you will be permitted to use both sides. Formula sheets will be provided and will be posted in advance of the exam.

Dates will be announced. Please check the course schedule for full details.

Academic integrity

The giving of assistance to or receiving of unauthorized assistance from another person, or the use of unauthorized materials during University Examinations can be grounds for disciplinary action, up to and including expulsion from the University. Course grading will proceed in compliance with University policy as given in Article 3, Part 1 of the Student Code.

Please be aware that prior to or during an examination the instructional staff may wish to rearrange the student seating. Such action does not mean that anyone is suspected of inappropriate behavior.

Plagiarism and cheating will not be tolerated and will be grounds for disciplinary action.