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Should I learn Classical Mechanics before Electricity & Magnetism?

  1. Mar 1, 2008 #1
    I will probably be taking both CM I/II and E&M I/II before I graduate, but I'm wondering is it a bad idea to take E&M before taking CM?

    I don't think I can take both at the same time this coming year so I have to pick just one.
  2. jcsd
  3. Mar 1, 2008 #2
    Without a doubt, take CM before E&M.
  4. Mar 1, 2008 #3
    just curious, why do you say definitely CM first?
  5. Mar 1, 2008 #4
    Well, E&M relies on many of the concepts in CM. For example, I think one would need to understand gravitational potential energy before electric potential.
  6. Mar 1, 2008 #5
    Yes, you get introduced to many concepts in CM, whereas in E&M you are expected to have already seen them, and they are just modified for that class.

    So for example things like rotating frames, the 1/r potential, etc. Trying to learn all about that AND learn E&M would be tough.
  7. Mar 1, 2008 #6
    I would also say take classical before E&M. E&M is hard for most people, its best to have at least one or two advanced courses before taking it. Im assuming your CM is a course based on the lagrangian and Hamiltonian methods though.
  8. Mar 1, 2008 #7
    The book for CM that is used here is Thornton & Marion, I don't think Lagrangian and Hamiltonian's are taught until a Goldstein level class though.

    Does Thornton & Marion require knowledge of ODE's? How about Kleppner?

    I haven't taken ODE yet and I guess it's going to hold me back in physics soon.
  9. Mar 2, 2008 #8


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    At my school, the [undergraduate, upper division] Classical Mechanics and Electricity & Magnetism are taken simultaneously by students; I did not experience any problems with this when I took the classes.

    The Thornton & Marion book does cover Lagrangian and Hamiltonian mechanics. Will your course just be skipping this topic, or are you just guessing?

    You will be expected to have some knowledge of ordinary differential equations…or rather you’ll need to know how to solve them by the ‘method of assumption’ (i.e. solve ODEs which you already know the solution too, for example simple harmonic oscillators).
  10. Mar 2, 2008 #9
    Do you guys go straight to Marion? I thought that book needs a prereq of basic physics first.
  11. Mar 2, 2008 #10
    In most schools the upper division CM does require the introductory Physics class.

    The course description of the CM class states it covers Lagrangian and Hamiltonian mechanics.

    Guess I'll have to talk to the professors, the class description says it doesn't require any math above Calc I, but the class might go into ODE type material.
  12. Jan 23, 2009 #11
    Last semista,i tok both CM & E&M,wel if i were u, i wud go for CM first as it wil give u maths skils & manipulations that will help u in other physics courses. including E&M.
  13. Jan 23, 2009 #12
    Classical Mechanics first, Electromagnetism second. Science is a building : to get to the top, it's way better taking all the steps instead of jumping 3-4 steps each time. Classical Mechanics (the basics) is the first step, and it's before Electromagnetism for the same reasons above : you need many concepts of CM to understand Electromagnetism.

    But, that's the way electromagnetism books are made : they often take for granted that you understand these concepts very well. If you find an E&M book such as all these concepts are explained clearly, as if it was the first time you're learning about it, then you can start learning it. But I very much doubt that such a book exist.
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