It then
follows that the right plate of C1 has charge –Q
and the left plate of C2  has charge Q If this was
not so, the net charge on each capacitor would
not be zero This would result in an electric field
in the conductor connecting C1and C2 Charge
would flow until the net charge on both C1 and
C2 is zero and there is no electric field in the
conductor connecting C1 and C2