Dielectrics
Inserting a non-conducting material between the plates of a capacitor changes the VALUE of the capacitance.
The dielectric constant of a material is the ratio of the capacitance when filled with the dielectric to that without it. i.e.
- k values are always > 1 (e.g., glass = 5.6; water = 78)
- They INCREASE the capacitance of a capacitor (generally good, since it is hard to make “big” capacitors
- They permit more energy to be stored on a given capacitor than otherwise with vacuum (ie, air)