An ideal air-filled parallel-plate capacitor has round plates and carries a fixed amount of equal but opposite charge on its plates. All the geometric parameters of the capacitor (plate diameter and plate separation) are now DOUBLED. If the original energy stored in the capacitor was I-JOY, how much energy does it now store?

AWE/d where C= capacitance, A= area, d= distance between plates let original radius be r so original area A= Tall none r is doubled and d is also doubled o new area AAA also new distance do= ad so new capacitance CNN=AAA/E(ad) = AAA/De = C as only geometric changes are done but charges on plates will retrain same so original energy stored in capacitor I-Joy= 0. 5(Q/C) new energy stored in capacitor battery.

How much work was done in charging this capacitor? Work done = joule. A cylindrical capacitor is made of two thin-walled concentric cylinders. The inner cylinder has radius RL = 4. 0 mm, and the outer one a radius or= 8. 0 mm. The common length of the cylinders is L = 150 m. What is the potential energy stored in this capacitor when a potential difference