Lesson: Electric Field in a Dielectric
In this lesson, we will learn how to relate the variation in capacitance to electric field strength in a dielectric and how this defines dielectric strength.
Sample Question Videos
Worksheet: 5 Questions • 1 Video
What is the potential difference between the plates of the capacitor before the dielectric has been inserted?
What is the potential difference between the plates of the capacitor after the dielectric has been inserted?
Before the dielectric is inserted, what is the electric field magnitude at the point midway between the plates?
After the dielectric is inserted, what is the electric field magnitude at the point midway between the plates?
The dielectric to be used in a parallel-plate capacitor has a dielectric constant of 3.60 and a dielectric strength of V/m. The capacitor has to have a capacitance of 1.25 nF and must be able to withstand a maximum potential difference 5.5 kV. What is the minimum area the plates of the capacitor may have?
What is the maximum permissible voltage across the capacitor to avoid dielectric breakdown?
What is the surface charge density on the surface of the dielectric when the capacitor is at the maximum voltage at which it avoids dielectric breakdown?