2 Consider the circuit shown in Fig.5, consisting of a battery of voltage E, a switch S, and a parallel-plate capacitor with capacitance C. The capacitor con- sists of two parallel conducting plates of equal area A separated by a distance d. After the switch S is closed and the capacitor is fully charged, a conducting plate of thickness d/3 and area A is inserted slowly between the plates of the capacitor. The inserted conducting plate is kept parallel to the conducting plates of the capacitor. Select answers to the questions from (a) to (z) below, and write the symbol of the answer in the box. (1) Find the capacitance of the capacitor after the conducting plate is inserted. (2) How much is the increase in the charge stored in the capacitor caused by in- serting the conducting plate? (3) How much is the increase in the energy stored in the capacitor caused by in- serting the conducting plate?

2 Consider the circuit shown in Fig.5, consisting of a battery of voltage E, a switch S, and a parallel-plate capacitor with capacitance C. The capacitor con- sists of two parallel conducting plates of equal area A separated by a distance d. After the switch S is closed and the capacitor is fully charged, a conducting plate of thickness d/3 and area A is inserted slowly between the plates of the capacitor. The inserted conducting plate is kept parallel to the conducting plates of the capacitor. Select answers to the questions from (a) to (z) below, and write the symbol of the answer in the box. (1) Find the capacitance of the capacitor after the conducting plate is inserted. (2) How much is the increase in the charge stored in the capacitor caused by in- serting the conducting plate? (3) How much is the increase in the energy stored in the capacitor caused by in- serting the conducting plate?