A parallel-plate air capacitor of capacitance is connected to a battery
PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Electric Force Field and Potential · Electric Force Field and Potential
Problem
A parallel-plate air capacitor of capacitance 100pF is connected to a 200V battery. A dielectric slab of relative permittivity κ=5 is then completely inserted between the plates while the capacitor remains connected to the battery.
(i) Calculate the charge on the capacitor and the energy stored in it before the slab is inserted.
(ii) Calculate the charge and the energy stored after the slab is fully inserted.
(iii) Determine the ratio of the final energy to the initial energy.