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

Electric dipole moment

  1. May 5, 2012 #1
    What is the physical meaning of electri dipole moment? What does it tell us about the dipole?
    Please don't just throw away mathematical equation (p=qd r_hat); help me to get its physical sense!
     
  2. jcsd
  3. May 5, 2012 #2

    jtbell

    User Avatar

    Staff: Mentor

    What happens when you put an electric dipole in an electric field?
     
  4. May 5, 2012 #3
    it experiences torque.
     
  5. May 5, 2012 #4
    Do you know what the physical meaning of the moment of inertia is? I've found that questions like this in a Physics class will almost always be answered with, "It's a collection of symbols we see often enough to give it a special name."

    That being said, it's a measurement of the distance between the positive and negative charges in an electric dipole for a simple two charge dipole multiplied by the magnitude of one of the charges. That's a pretty physical meaning for it. It shows up in the math when we ask questions like what kind of Torque does the dipole experience when placed in an electric field. When we crunch the numbers we keep seeing a charge multiplied by a distance and we call it a 'moment' for convenience, because that's what we called it the last time we saw it ; )
     
  6. May 5, 2012 #5
    For example ,if u ask what is energy,we can say like its capacity of doing work!for force we can experience it.Like them what does electric dipole moment signify ?? U mean that its just collection of symbols named as electric dipole moment?o_0
     
  7. May 5, 2012 #6
    Energy is a great example, Feynman used to describe it as a convenient check list to keep track of the parts of a system as they interact. Saying it is related to the capacity to do work isn't anymore physical than saying the electric dipole moment is related to the dipole's capacity to experience a torque in an electric field.
     
  8. May 5, 2012 #7

    jtbell

    User Avatar

    Staff: Mentor

    OK! So the dipole moment, in practical terms, quantifies the tendency of an object to experience a torque when placed in an electric field. The larger the dipole moment, the larger the torque. (keeping the orientation the same, of course)
     
  9. May 6, 2012 #8
    Thanks!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Electric dipole moment
  1. What is dipole moment? (Replies: 2)

  2. Electric dipole (Replies: 2)

  3. Electric Dipole Moment (Replies: 2)

Loading...