A 10.0-F parallel-plate capacitor is connected to a 12.0-V battery. After the capacitor is fully charged, the

Question:

A 10.0-µF parallel-plate capacitor is connected to a 12.0-V battery. After the capacitor is fully charged, the battery is disconnected without loss of any of the charge on the plates.
(a) A voltmeter is connected across the two plates without discharging them. What does it read?
(b) What would the voltmeter read if (i) the plate separation were doubled; (ii) the radius of each plate were doubled and, but their separation was unchanged?