Answer:
option (b), (c), (g)
Explanation:
When the battery is disconnected, the charge on the plates of a capacitor remains same.
As the capacitance of the capacitor is directly proportional to the dielectric constant.
C = k C0
Now the charge remains same, So
Q = Q0
Q = k C0 x V0 / k
So, potential between the plates is V0 / k.
Energy, E = 1/2 x C X V^2 = 1/2 x k C0 x V0^2 / k^2 = E0 / k
So, energy becomes E0 / k.