Yes, it should have one, nicely done Lightarrow :). Now we just have to put it into consideration by shoving the resistance experienced by, for example a bit of invariant mass, like a human moving inside and relative that EM-field. If we then finally convert it into Joules to describe the energy, we finally will know why we don't turn on our telly, preferring that good book instead. Yes, it's easier to let it be :)
So what would the density be?