In Week 12 we shall extend our discussion of radiation to include harmonically varying sources of radiation.

There are two interactive sessions each week.

There are no mini-lectures in this last week of the course to give you time to review the course. Remember there is a course summary and some comments on the format and style of the exam. ..... Please let me know if you find any typos or other mistakes!

⚬ Monday 9:00 - Live Lecture - Harmonically varying sources of radiation (electric dipole)

N.B. This live lecture covers material that is not covered in any mini-lecture.

Unfortunately the AV system in the lecture theatre was broken and I had to write on the board. Here is an Audio only Lecture 23 recording.

Here is a video of last year's Lecture 23 (Starts with animations of radiation patterns and then goes on to dipole radiation):

Lecture 23 Podcast ............. Notes written to visualiser

You can find here a link to the Jupyter notebook for the animation of the radiation pattern produced by an oscillating electric dipole that I have used in this lecture.

⚬ Wednesday 11:00 - Christmas-themed worked example (with chocolate ;-)

Christmas-Themed Electrodynamics Question ............. Notes written to visualiser ............. Notes on Q2 (not covered due to lack of time in the lecture)

Optional preparation for this session: you might want to revise

Mini-Lecture 5: Multipole Expansions in Electrostatics ............. Lecture notes written to visualiser

and

Live Lecture 14: The potentials produced by a point charge moving with constant velocity

N.B. you may also like to think about the puzzle I presented starting at about 11 minutes into the podcast of the Wednesday lecture in week 11! There will be a special chocolate prize for people who have contributions to a discussion on this topic in today's session!

Revision of multipole expansions in electrostatics and magnetostatics.

In preparation for Monday's lecture on harmonically varying sources you may wish to revise the mini-lectures on multipole expansions

Mini-Lecture 5: Multipole Expansions in Electrostatics ............. Video ............. Lecture notes written to visualiser

Mini-Lecture 7c: Multipole Expansions in Magnetostatics ............. Video ............. Lecture notes written to visualiser

Alternative treatments of harmonically varying sources.

D.J. Griffiths, Introduction to Electrodynamics: Chapter 11.1. (N.B. if in your edition of Griffiths, chapter 11 in entitled "Electrodynamics and Relativity" then try looking in chapter 10!)

M.A. Heald and J.B. Marion, Classical Electromagnetic Radiation (3rd edition): Chapter 9.1, 9.2, 9.8

J.D. Jackson, Classical Electrodynamics: Chapter 9.1-9.3.

Look at the