Capacitance

""energy is the capacity of work done by a particle""..the definition we learnt in class 8 may be.

so now, what we do is put a charge in the space b/w the 2 plates of capacitor.
its velocity increases on its own or in other words its kinetic energy changes itself or work is done on it.

now by the definition of field, it is the field which applies the force and not the charges.

the charges create a field and this field in turn exert force on other charges appearing in it. if i m nt wrong something like this is written in all physics books.

so the work is done by the place where the field exists i.e. the energy is stored only in the place where field is existent.

thus it is the space between the 2 capacitor plates.

cheers!!