In the circuit shown (figure1), all the switches are open initially and all capacitors are uncharged. Now first only  $S_1$ is closed and open when steady state is reached, then  $S_2$ is closed and open when again steady state is reached, after this $S_3$  is closed and open when steady state is reached, this process repeated continuously. After closing sixth switch, the fourth capacitor (8C) is removed and connected (say at t = 0) to an uncharged capacitor of original capacitance C which now has a dielectric (dielectric constant 2) filling half its volume (see figure2), through a resistor R.