1. The problem statement, all variables and given/known data A capacitor, is fully charged by a battery. The battery is disconnected and a dielectric is inserted into the capacitor. Which of the following is true? I. Voltage will stay the same II. Potential energy of the capacitor will increase III. capacitance will increase 2. Relevant equations U = 0.5 * Q * deltaV 3. The attempt at a solution I know that III is true as dielectrics by definition increase capacitance. How can I eliminate the other two to get the final answer of III only? Thanks in advance.