13. A 10.0 µF capacitor is charged to a potential difference of 60 V. The terminals of the charged capacitor are
then connected to those of an uncharged 30.0 µF capacitor.
(a) Compute the original charge of the system.
(b) Compute the final potential difference across capacitor.
(c) Compute the final energy of the system.
(d) Compute the decrease in energy when the capacitors are connected.