E-1
A cone with a circular base of radius 2.00 cm and
height 3.00 cm is situated in a uniform electric field
of magnitude 3.5 x 104 N/C making an angle 40o
with the perpendicular to the base. There is no
charge inside the cone. What is the flux through the
sides of the cone.
Ans. 33.7 N m2/C
E-2
Two charged concentric cylinders of infinite length
have radii 4.00 and 6.00 cm. The charge per unit
length on the inner cylinder is 2.0 x 106 C/m and on
the outer cylinder –2.0 x 106 C/m. Find the electric
field at a point 5.00 cm from the axis of the
cylinder.
E-3
The intensity of the earth’s electric field near its
surface is 130 N/C, pointing toward the center of
the earth. What is the charge of earth, assuming it
is uniformly distributed?
E-4
What is the electric field between two parallel plate
infinite planes of charge, one with a charge per unit
area 6 x 10-7 C/m2 and the other with charge per
unit area 9 x 10-7 C/m2?
E-5
A conducting spherical shell of radius 10 cm
carries a net charge of –2 C uniformly distributed
on its surface, Find the electric field at a point 15
cm away from the center of the shell.
E-6
A square sheet of copper of sides 20 cm is placed
in an extended electric field of 5 x 103 N/C directed
perpendicular to the sheet. Find the charge density
of each face of the sheet.
E-7
A solid conducting sphere of radius [a] has a net
positive charge of [3 Q]. Concentric with this
sphere is a thin conducting spherical shell of radius
[b > a] which has a net negative charge of
magnitude Q. Find the electric field at a distance
3b.
E-8
A point charge is placed at the center of an
uncharged hallow conducting sphere. The inside
radius of the sphere is [a], and the outside radius is
[b], What is the induced charge per unit area on the
inner surface of the hallow sphere?
Chapters 24 (021)
The cube in figure 3 has edge lengths of 2.00 m and is
oriented as shown in a region in which a uniform electric
field exists. The electric field is given by: (-5.00 i + 8.00
k) N/C, where i and k are unit vectors parallel to the xaxis and z-axis respectively.
Find the electric flux through the right face (shaded)of
the box.
A1
A2
A3
A4
A5
zero
-10.0 N.m**2/C
+16.0 N.m**2/C
+6.00 N.m**2/C
+26.0 N.m**2/C
Figure 4 shows cross-sections through two large, parallel
non-conducting sheets with identical distributions of
negative charge. The surface charge density for each
sheet is 7.00*10**(-15) C/m**2.
What is the electric field at point A?
A1
A2
A3
A4
A5
7.91*10**(-4) N/C
7.91*10**(-4) N/C
3.96*10**(-4) N/C
3.96*10**(-4) N/C
0
downward
upward
upward
downward
Two long, charged, concentric cylindrical shells have
radii 3.0 and 6.0 cm. The charge per unit length is 2.00*10**(-6) C/m on the inner cylinder and
+5.00*10**(-6) C/m on the outer cylinder. Find the
electric field at r = 4.0 cm, where r is the radial distance
from the common central axis.
A1
A2
A3
A4
A5
9.00*10**5
9.00*10**5
22.5*10**5
13.5*10**5
13.5*10**5
N/C
N/C
N/C
N/C
N/C
radially inward
radially outward
radially inward
radially outward
radially inward
An isolated conductor of arbitrary shape has a net charge
of +20*10**(-6) C. Inside the conductor is a cavity
within which is a +5*10**(-6) C point charge.
Find the charges on the cavity wall and on the outer
surface of the conductor.
A1 -5*10**(-6) C , +25*10**(-6) C
A2 -5*10**(-6) C , +15*10**(-6) C
A3 -5*10**(-6) C , +20*10**(-6) C
A4 -20*10**(-6) C , +25*10**(-6) C
A5 +5*10**(-6) C , -25*10**(-6) C