hwk 8-1. Given the capacitor as described, the electric field is constant everywhere inside the plates and directed left to right. It's value is E = Q/(ıR2 e0) .
Since DV=
-E. DL
= - E DL cos u,
where u is the angle between E and
DL DVDC
= DVAD = 0, (cuz u = 90°),
anD
a-1) DVABC = DVAB
+ DVBC = - E s1
cos(180°) + 0 = E s1.
a-2) DVAC = -E DL cos u = -E (-s1) = E s1 (see figure at right )
a-3) DVADBC = DVAD
+ DVDB + DVBC
= 0 + (-E)(-s1) + 0 = E s1
b) DVAC =
Hwk8-2: Have DVAB = 1.5 V
Which end has higher potential? B
Magnitude and direction of E inside the resistor? E =
1.5V / 10-2 m = 1500 V/m toward A.