Q.

A parallel plate capacitor with plate separation 5mm is charged up by a battery. It is found that on introducing a dielectric sheet of thickness 2 mm, while keeping the battery connections intact, the capacitor draws 25% more charge from the battery than before. The dielectric constant of the sheet is __________.            [2024]


Ans.

(2)     Without dielectric Q=A0dV

           with dielectric

                         Q=A0Vd-t+tK

           Given A0Vd-t+tK=(1.25)A0Vd

            1.25(3+2K)=5K=2