1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

I Particle in an Electromagnetic Field

  1. Jan 27, 2017 #1
    Using the Lagrangian : L = ½mv^2 - qφ + qAv

    What is the physical intuition of Av ? I know that A is the magnetic vector potential and that v is the velocity of the charged particle. I just don't know what their dot product means physically .
  2. jcsd
  3. Jan 28, 2017 #2


    User Avatar
    Science Advisor
    Homework Helper
    2017 Award


    I find your expression hard to read/interpret. Fortunately, it's all chewed out thoroughly here . With the 'explanation':
    In other words: if you start with the Lorentz force law and do the math backwards (ahem) you (can) end up with this form for the Lagrangian.

    "It works" is a also a good argument for a physicist ( I try to avoid the word intuition )
  4. Jan 28, 2017 #3
    Well, 1/2mv^2 is kinetic energy of the particle , qφ is the coulomb potential of electricity . So we know what the other components of the equations are. So my question really is what does the term qvA mean ? It's something to do with magnetism, but what exactly ?
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted