(a) A parallel plate capacitor is constructed with two plates of area 0.0280 m^2 and separation 0.550 mm. The space between the plates is filled with a dielectric constant κ. When the capacitor is connected to a 12.0 V battery, each of the plates has a charge of 3.62 × 10^(-8) C. (a) What is the value of the dielectric constant?
(b) A 0.40 μF capacitor is connected to a 9.0 V battery. How much charge is on each plate of the capacitor?