All lecture recordings are available at: https://mediaspace.illinois.edu/channel/PHYSICS+225+FALL+2021/221232443/subscribe.
Click the "Subscribe" button to automatically be notified when new recordings are uploaded.

Discussion Units

Unit	Topic	Discussion Answers	Lectures	Videos
1 (Aug 22-28)	Special Relativity: Do You c What I c?	Solutions 1	Lecture 1	Video 1
2 (Aug 29-Sept 4)	The Lorentz Transformation	Solutions 2	Lecture 2	Video 2
3 (Sept 5-Sept 11)	The Interval, Causality, and Proper Time	Solutions 3	Lecture 3	Video 3
4 (Sept 12-Sept 18)	4-vectors, Tilted Axes, and the Expanding Universe	Solutions 4	Lecture 4	Video 4
5 (Sept 19-Sept 25)	E = mc²	Solutions 5	Lecture 5	Video 5
6 (Sept 26-Oct 2)	Conservation, Conversion, and Nuclear Power	Solutions 6	Lecture 6	Video 6
7 (Oct 3-Oct 9)	The 4-vectors of dynamics	Solutions 7	Lecture 7	Video 7
8 (Oct 10-Oct 16)	Differential Calculus in 3D	Solutions 8	no lecture due to in-class midterm	no video
9 (Oct 17-Oct 23)	Vector Fields and Curvilinear Coordinates	Solutions 9	Lecture 9	Video 9
10 (Oct 24-Oct 30)	The Line Element and Grad, Div, Curl	Solutions 10	Lecture 10	Video 10
11 (Oct 31-Nov 6)	Multi-dimensional Integration I	Solutions 11	Lecture 11	Video 11
12 (Nov 7-Nov 13)	Multi-dimensional Integration II and Maxwell's Equations	Solutions 12	Lecture 12	Video 12
13 (Nov 14-Nov 20)	The Zen of i	Solutions 13	Lecture 13	Video 13
14 (Nov 28-Dec 4)	Pitfalls & Mastery	Solutions 14	Lecture 14 (finals wrap-up)	Video 14