PHYS 1B Lecture Notes - Lecture 11: Relative Permittivity, Dielectric, Electric Current
Document Summary
The formula we derived earlier for a parallel plate capacitor assumed empty space between the plates: We can also increase the capacitance of a capacitor by inserting a dielectric (insulating) material between the plates. Where k is a unitless variable called the dielectric constant of the insulating material. K is determined experimentally as :k = (cdielectric filled)/(c empty) Current, i, is the rate of flow of charged particles through conductive material. Resistors use geometric and material properties to slow the flow of charged particles. The conversion of the kinetic energy of the moving charged particles into other forms of energy produce light and heat. Power delivered depends on the current and voltage. When we combine capacitors with resistors, we observe exponential charging and discharging. Consider a charged particle in an electric field as it moves through a solid. The charged particle will make many elastic collisions with other electron sin the metal.
