  As it is well-known one of the most fascinating examples in remarkable
discussion between Einstein and Bohr on the conceptual foundation of the
quantum mechanics (Heisenberg energy-time uncertainty relation especially) was
an experimental device representing a box hanged on an elastic spring. The pair
of similar devices is used in this work for formulation of a classical and
(implicitly) quantum mechanical analog of the famous two capacitors paradox. It
admits a simple solution of the paradox since energy difference or seeming
paradoxical "loss" can be explained by work of the elastic force for moving of
the boxes in the gravitational field. (Obviously, original two capacitors
paradox can be explained in the analogous way.)
