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Re: Energy density; the correct one



Whoa!

David Rutherford wrote:



W = \int{q*(-d(phi)/dr)*dr}

or

W = \int{q*(-d(phi)}


IMHO - The scond equations is incorrect! - because the second dr in the first
equation is 0. Actually performing \int involves a path, not just a change in phi
for reasons independent of dr.

You can change the energy of q by changing potential (by moving other charges),
but it's not work done on q itself, V has changed because of energy input
elsewhere in the q1-field-q2 configuration.

Maybe I'm seeing this totally wrong - I'd appreciate a clarification if I am.

Bob at PC