A parallel-plate capacitor consists of two square plates 11 cm on a side, spaced 0.40 mm apart with only air between them. What is the maximum energy that can be stored by the capacitor? The dielectric in a capacitor serves two purposes. It increases the capacitance, compared to an Express your answer in joules. otherwise identical capacitor with an air gap, and it increases the maximum potential difference the capacitor can support. If the electric field in a IVO AED material is sufficiently strong, the material will suddenly become able to conduct, creating a spark. The critical field strength, at which breakdown U air= 2.07 . 10 5 occurs, is 3.0 MV /m for air, but 60 MV /m for Teflon. Submit Previous Answers Request