PHYSICS 4B EQUATION SHEET
kq1q2
F12
E
E
r
2
Coulomb’s Law
rˆ12
F
q
Electric Field
C
q
rˆ
r2
dq
k 2 rˆ
r
2k
r
Electric Field due to a
point charge
Eo
k
1
U
CV 2
2
dQ
I
dt
I
J
A
J
E
k
E
E
E
Electric Field due to a
continuous charge
E-field due to infinite line
of charge
E-field due to an infinite
plane of charge
2
o
E-field just outside a
conductor
E
o
E
E dA
E
E dA
Electric Flux
qenc
V
U
q
VB VA
E
R
V
Gauss’s Law
o
p qd
τ p E
U
p E
Electric Dipole Moment
Torque on Electric Dipole
PE of electric dipole
B
Electric Potential
E ds Difference
A
Energy Density in an
E-field
Capacitance with
Dielectric
E-field with Dielectric
1
2
oE
2
kCo
Energy in a Capacitor
Electric Current
Current Density
Ohm’s Law
Resistance
A
IR
1
“Ohm’s Law”
Resistivity
Req
R1 R2
Resistors in Series
1
Req
1
R1
Resistors in Parallel
V
I (t )
e
R
1
R2
Current Charging
Capacitor
t
t
qV
kq1q2
U
r
kq
V
r
dq
V k
r
E
V
Q
C
V
oA
C
d
Ceq C1 C2
Electric Potential Energy
Electric Potential Energy
1
Ceq
Capacitors in Series
U
1
C1
1
C2
Electric Potential due to a
point charge
q (t ) CV (1 e
RC
F qv B
F
IL B
F
I ds B
Electric Potential due to an
extended body of charge
Relation between V and E
Capacitance
b
a
τ μ B
Capacitance for ParallelPlate Capacitor
U
μ B
Capacitors in Parallel
F
qE qv B
IB
VH
nqt
)
Charge Charging
Capacitor
Time-Constant
Magnetic Force on a
Moving Charge
Magnetic Force on a
Current-Carrying
Conductor
Magnetic Force on a
Current-Carrying
Conductor
Torque on Current
Loop
Magnetic Potential
Energy
Lorentz Force
Hall Voltage
1
B
dB
B
Ids rˆ
o
4
o
r
qv rˆ
4
B d
r
o (I
o
B
o nI
Id )
E
dt
d
N
L
N
d
B
dt
B
I
V
(1 e
R
L
R
1 2
U
LI
2
VR
VL
I p X L sin
t
Vc
I p X c sin
t
t
B
dt
d
2
Vp
2
L
1
C
I p R sin
Xx
B
dt
E ds
Vrms
XL
B dA
B
I
I rms
2
d
Id
L
M12
2
B2
2 o
N 2 12
I1
Ip
dI
L
dt
2
2
2
Pave I rms
R
V I pZ
Z
t
)
o
R 2 ( X L X c )2
X L Xc
tan 1
R
1
LC
2