Two 5.0 mm x 5.0 mm electrodes are held 0.10 mm apart and are attached to a 9.0 V battery. Without disconnecting the battery, a 0.10-mm-thick sheet of Mylar is inserted between the electrodes. What are the capacitor's potential difference, electric field, and charge (a) before and (b) after the Mylar is inserted?
Hint: Section 26.7 considered a capacitor with isolated plates. What changes, and what doesn't, when the plates stay connected to the battery?