Download Electric current is the net charge unit time

Electric current is the net charge
that flows through a surface per
unit time
Ohm’s law: The resistivity (or
conductivity) of a material is
independent of the magnitude and
direction of the applied electric field.
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Electric current is the net charge
that flows through a surface per
unit time
i
dq
dt
q   idt
Current density j = i/A
 
i   j  dA


j  envd

vd
is the drift velocity
j,E
vd
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Ohm’s law: The resistivity (or
conductivity) of a material is
independent of the magnitude and
direction of the applied electric field.


j  E


E  j
R
V
I
R
L
A
Capacitor
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Parallel plate capacitor
Spherical and cylindrical capacitor
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Parallel combination of capacitors
Series combination of capacitors
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Capacitor with a dielectric
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