1) If a 4- F capacitor and an 8- F capacitor are connected in parallel, which has the larger...
-
date post
21-Dec-2015 -
Category
Documents
-
view
220 -
download
3
Transcript of 1) If a 4- F capacitor and an 8- F capacitor are connected in parallel, which has the larger...
1) If a 4-F capacitor and an 8-F capacitor are connected in parallel, which has the larger potential difference across it? Which has the larger charge?
Quiz
2)
Two capacitors are connected in series as shown. If they were initially uncharged, what will be the charge inside the dotted box after connecting points A and B to a battery of voltage V?
A B
3) If the wire connecting the capacitors is bent so that capacitors look like
A
B
how do you now call the arrangement?
a
b
C1C3
C5C4
C2
C1=C5=8.4 F and C2=C3=C4=4.2 F The applied potential is Vab=220 V. a)What is the equivalent capacitance of the network
between points a and b? b) Calculate the charge on each capacitor and the
potential difference across each capacitor.
ticselectrostainrdE 0
E
0 rdE
0 rdE
1E
2E
0)()( 2121 CDEABErdErdED
C
B
A
A
B C
D
!21 impossibleEE
Electric field near the surface of a conductor
0
E
L
A
AQL
Q
V
QC 0
0
Capacitors in series: ...1111
321
CCCCtot
Capacitors in parallel: ...321 CCCCtot
22
2
1
2
1Q
CCVW
faradC ][
Insulating sphere with charge Q uniformly spread throughout the volume
A
E
r
204
1
r
QEAr
rA
QEAr
304
A
Conducting sphere with charge Q
A
E
r
204
1
r
QEAr
0 EAr
V
r
A
A
Q
04
1
r
QVAr
04
1
A
QVAr
04
1
Current, Ohm’s Law, Etc.
dt
dQi
)(;:' VoftindependenConstRi
VRLawsOhm
A
lR
Ej
jE
t
Qiave
dt
dQ
t
Qi
t
0
lim
Consti
VLawsOhm :'
,Ri
V where R is resistance
Resistance does not vary with the applied voltage
resistor
Ampere
VoltsR
Experimentally it is found that R depends on the material the wire is made of and its dimensions. Does not depend on the shape.
A
lR
areatheisAlengthisl ,
yresistivitis
tyconductiviis
1
+
-V i
l
VA
l
VA
R
Vi
1
i