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16.360 Lecture 20. Today. Conductors Resistance Dielectrics Electric boundary conditions Capacitance Electrostatic potential energy Image method. 16.360 Lecture 20. Conductors. Electron drift velocity. Hole drift velocity. Conducting current. Point form of Ohm’s law.
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16.360 Lecture 20 Today • Conductors • Resistance • Dielectrics • Electric boundary conditions • Capacitance • Electrostatic potential energy • Image method
16.360 Lecture 20 Conductors Electron drift velocity Hole drift velocity Conducting current Point form of Ohm’s law
16.360 Lecture 20 Resistance General form
16.360 Lecture 20 Joule’s law General form
16.360 Lecture 20 Dielectrics Electrical field induced polarization
16.360 Lecture 20 Dielectrics P: electric polarization field For homogeneous material: Electric susceptibility Relative permittivity: Dielectric breakdown
16.360 Lecture 20 Electric boundary condition the tangential component is continuous across the boundary of two media.
16.360 Lecture 20 Electric boundary condition the normal component of D changes, the amount of change is equal to the surface Charge density.
16.360 Lecture 20 Dielectric-Conductor boundary
16.360 Lecture 20 Conductor-Conductor boundary
16.360 Lecture 20 Capacitance
16.360 Lecture 20 Electrostatic Potential Energy Image Method Any given charge above an infinite, perfect conducting plane is electrically equivalent to the combination of the give charge and it’s image with conducting plane removed.