The stored electrical energy of such a system is, (7.3) Since this energy changes as the geometry (and hence C) changes, it must require work to move the plates of a capacitor.
(it; must require; work; to move the plates of a capacitor) Context(it must require,List([121, 136))):(The stored electrical energy of such a system; is; 7.3) Since this energy changes as the geometry (and hence C) changes) Context(The stored electrical energy of such a system is it must require,List([0, 136))):(this energy; changes; as the geometry (and hence C) changes)
it must require,List([121, 136)) The stored electrical energy of such a system is it must require,List([0, 136))
it The stored electrical energy of such a system this energy
must require is changes
work to move the plates of a capacitor
7.3) Since this energy changes as the geometry (and hence C) changes
as the geometry (and hence C) changes