Lecture ( 8 ) Relationship between E and V – Maxwell’s

Relationship between E and V – Maxwell’s Equation
If any charge is move inter electric field effect by force
F ?= q_o E ?
The work done from this force is equal to
dw= F ? .(ds) ? = q_o E ? .(ds) ?

?w= q_o ?_i^f??E ? ? .(ds) ?
? V= (-w)/q
V_f- V_i= - ?_i^f?E ? .(ds) ? (if vi is at point zero)
V= - ?_i^f?E ? .(ds) ?



2.10 An Electric Dipole
Let the electric dipole as shown in the figure, we want to find the electric field E ? at point ( p) along the axies of the dipole . Z
E = E ( + ) - E (- ) E ?_+
(E_- ) ?
( r+ )
( r- )
Z +q

( 0,0 ) d
-q















2.11 Energy Density in Electrostatic Fields (u J/m3)
Is the potential energy per unit volume between the plates [ ( A ) area of the parallel plate and ( d ) distance then (Ad ) volume between the plates ]

u= U/Ad
U= 1/2 C v^2
u= ?Cv?^2/2Ad
were
C= (?_o A)/d
u= 1/2 ?_o ?(v/d )?^2
But
E= v/d