Angular momentum of lectromagnetic fields?

AI Thread Summary
Electromagnetic fields possess both momentum and angular momentum, which can influence the torque on objects within these fields. Understanding these concepts is essential for grasping the dynamics of electromagnetic interactions. Resources like the Feynman Lectures Volume II, particularly chapters 27 and 28, provide clear explanations of electromagnetic energy, momentum, and the mass associated with these fields. These chapters are recommended for those seeking a deeper understanding in accessible language. Engaging with these materials can enhance comprehension of the angular momentum of electromagnetic fields.
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Angular momentum of lectromagnetic fields?!

Dear all,

I have recently read that an electromagnetic filed has has momentum and even angular momentum. For example, I read a paper in which the torque on a body in a magnetic field was calculated by taking the derivative of the angular momentum of the magnetic field! (We didn't have such topics in our textbooks when I was a student ) Perhaps people here can help me understand it easier and faster.

1. What does momentum and angular momentum of an electromagnetic field mean?
2. Do you know of some materials or tutorials to teach such topics in a simple language ?

Your help would be appreciated.
 
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Feynman Lectures Volume II Chapter 27 has an excellent discussion of electromagnetic energy and momentum, and it touches on angular momentum as well. After you're done with that chapter, I recommend reading chapter 28 on the mass stored in the electromagnetic field; it's my favorite chapter in the book.
 


Thanks. I found the lecture notes, chapter 27 and will study it when I'm free.
 

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