16.360 Lecture 19

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16.360 Lecture 19
Maxwell equations
E electric field intensity
D electric flux intensity
H magnetic field intensity
B magnetic flux intensity
? electrical permittivity ?magnetic
permativity
?v electric charge density per unit volume J
current density per unit area.
Electrostatics
Magnetostatics
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16.360 Lecture 19
Electrostatics
Volume charge density
Surface charge density
Line charge density
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16.360 Lecture 19
Current density J
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16.360 Lecture 19
Coulombs law
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16.360 Lecture 19
Electric field due to a charge distribution
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16.360 Lecture 19
Gausss law
Gausss law
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16.360 Lecture 19
Electrical scalar potential
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16.360 Lecture 19
Electrical potential due to point charge
Electrical potential due to continuous
distributions
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16.360 Lecture 19
Electric field as a function of Electrical
potential
Poisons equation
Poisons equation
Laplaces equation
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16.360 Lecture 19
Electrical properties of material

• conductor
• dielectric
• semiconductor

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16.360 Lecture 20
Conductors
Electron drift velocity
Hole drift velocity
Conducting current
Point form of Ohms law
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16.360 Lecture 20
Resistance
General form
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16.360 Lecture 20
Joules law
General form
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16.360 Lecture 20
Dielectrics
Electrical field induced polarization
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16.360 Lecture 20
Dielectrics
P electric polarization field
For homogeneous material
Electric susceptibility
Relative permittivity
Dielectric breakdown
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16.360 Lecture 20
Electric boundary condition
the tangential component is continuous across
the boundary of two media.
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16.360 Lecture 20
Electric boundary condition
the normal component of D changes, the amount of
change is equal to the surface Charge density.
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16.360 Lecture 20
Dielectric-Conductor boundary
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16.360 Lecture 20
Conductor-Conductor boundary
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16.360 Lecture 20
Capacitance
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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 its image
with conducting plane removed.