Recent content by sprayer_faust

I should have used \partial. So the first \partial couples with infinitesimal volume \partial \tau, and the second with \partial t. What I was getting at: \frac{\partial}{\partial \tau}(\frac{\partial W}{\partial t}) = \vec{E} \cdot \vec{J} \, , which you can't get to from the first equation...

I (and probably everyone) like to learn from books that describe the reasoning/philosophy behind the equations as much as possible, instead of "pluging this in and getting that" or even just dishing out "clearlys". There's a footnote to the word "clearly" in some online LaTex tutorial...

Hi. The potential difference/voltage between the battery poles tells you how much energy (in Joules) is available per unit of charge (1 As). Short: Higher voltage means a single charge carrier can do more work for you. A charge capacity of 9 Ah tells you, that the battery can drive a...