- #1
Seidhee
- 8
- 0
Hello,
I am reading the volume 2 of the Feynman's Lectures on Physics, and something is bothering me when he calculates the dipole moment of a single atom induced by an extern field :
https://books.google.co.uk/books?id=uaQfAQAAQBAJ&pg=SA11-PA2&lpg=SA11-PA2&dq=feynman+dipole+single+atom&source=bl&ots=6nmZCqHDMk&sig=cd6wOGCKh9E9227ZX-a8KKhTqlM&hl=fr&sa=X&ei=NuI8VbHdI8v9UOSvgOAD&ved=0CDEQ6AEwAQ#v=onepage&q=feynman%20dipole%20single%20atom&f=false
Indeed, he states that : " p = qex "
But why ? I would use in general : " p = Zqex " where Z is the number of electrons in the atom.
x is the displacement of the center of charges of the electrons, and thus x is also the displacement of each electron.
Could you explain his reasoning ? It is not the first time he uses a single electron charge instead of Z in his calculations, and I do not understand.
Thanks.
PS : And qe is obviously equal to the charge of one electron and note equal to Z*(charge), because he uses then e² = q²e/4piε0 (we can also see it in the mechanical equation of motion).
Moreover, when he the does his calculations for the Helium atom, he keeps using qe = charge of one electron and does not use a new value for Z. And that is exactly what I find weird: he gets the good results event without having taken Z = 2.
I am reading the volume 2 of the Feynman's Lectures on Physics, and something is bothering me when he calculates the dipole moment of a single atom induced by an extern field :
https://books.google.co.uk/books?id=uaQfAQAAQBAJ&pg=SA11-PA2&lpg=SA11-PA2&dq=feynman+dipole+single+atom&source=bl&ots=6nmZCqHDMk&sig=cd6wOGCKh9E9227ZX-a8KKhTqlM&hl=fr&sa=X&ei=NuI8VbHdI8v9UOSvgOAD&ved=0CDEQ6AEwAQ#v=onepage&q=feynman%20dipole%20single%20atom&f=false
Indeed, he states that : " p = qex "
But why ? I would use in general : " p = Zqex " where Z is the number of electrons in the atom.
x is the displacement of the center of charges of the electrons, and thus x is also the displacement of each electron.
Could you explain his reasoning ? It is not the first time he uses a single electron charge instead of Z in his calculations, and I do not understand.
Thanks.
PS : And qe is obviously equal to the charge of one electron and note equal to Z*(charge), because he uses then e² = q²e/4piε0 (we can also see it in the mechanical equation of motion).
Moreover, when he the does his calculations for the Helium atom, he keeps using qe = charge of one electron and does not use a new value for Z. And that is exactly what I find weird: he gets the good results event without having taken Z = 2.