EE Pro for TI - 89, 92 Plus
Equations - Capacitors & Electric Fields
16
Entered Values
Computed results
Solution -
Press
„
to display the input screen, enter all the known variables, and press
„
to solve the
selected equation set. The screen display above shows the computed results.
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ρ
N
'AEQWNQODUO
T
AEO
ε
T
%QORWVGF4GUWNVU
'T
A8O
17.3 Charged Disk
These two equations describe the electric field and potential along the vertical axis through the center of a
uniformly charged disk. The first equation defines the electric field along the z-axis of the disk with a radius ra
and charge density of
ρ
s, a distance z from the plane of the disk. The second equation computes the electrostatic
potential Vz at an arbitrary point along the z-axis.
Ez
s
r
z
ra
z
=
⋅ ⋅
⋅ −
+
F
HG
I
KJ
ρ
ε ε
2
0
1
2
2
Eq. 17.3.1
Vz
s
r
ra
z
z
=
⋅ ⋅
⋅
+
−
ρ
ε ε
2
0
2
2
e
j
Eq. 17.3.2
Example 17.3 -
A charged disc 5.5_cm in radius produces an electric field of .2_V/cm 50_cm away from the
surface of the disc. Assuming that relative permittivity of air is 1.04, what is the charge density on the surface of
the disc?
Entered Values
Computed Results
Solution
- Select the first equation by pressing
¸
key, press
„
to display the input screen for this
equation, enter all the known variables, and press
„
. The computed results are shown in the screen
display above.
-PQYP8CTKCDNGUTC
AEO
ε
T
'\
A8EO
\
AEO
%QORWVGF4GUWNVU
ρ
U
'AEQWNQODO@