Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Third law reaction question

  1. May 10, 2003 #1
    I have attached a drawing that depicts the situation of two electromagetic coils in space seperated by a vast distance. It seems to me that in this case there would be a magnetic action force on the right coil but no reaction on the left coil. I'm probably missing something here but I would appreciate any pointers on what that might be. If the description or graphic is unclear, please let me know.


    Last edited by a moderator: May 10, 2003
  2. jcsd
  3. May 12, 2003 #2
    Newton's third law (in fact, the force concept as such) only holds if the propagation speed of the interaction is infinite. I have examined a similar problem (a retarded interaction when the objects are moving relatively to each other) on my webpage http://www.physicsmyths.org.uk/retard.htm.
  4. May 13, 2003 #3
    Thomas, may be you need to use Lorents transformations (instead of Galilean) between systems?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook