An isolated capacitor with capacitance C = 1 µF has a charge Q = 45 µC on its plates.
a) What is the energy stored in the capacitor?
Now a conductor is inserted into the capacitor. The thickness of the conductor is 1/3 the distance between the plates of the capacitor and is centered inbetween the plates of the capacitor.
b) What is the charge on the plates of the capacitor?
c) What is the capacitance of the capacitor with the conductor in place?
d) What is the energy stored in the capacitor with the conductor in place?