# Question bank

```GURU TEGH BAHADUR INSTITUTE OF TECHNOLOGY
Electromagnetic Field Theory
(4th Semester)
QUESTION BANK
(Based on Numericals)
1. A boundary exists at z=0 between two dielectrics, ππ1 =2.5 region z&lt;0 and
ππ2 =4 region z&gt;0. The field in region ππ1 is
πΈβ1 = −30π₯Μ50π¦Μ + 70π§Μ V/m
Find
(a) Normal component of πΈβ1
(b) Tangential component of πΈβ1
(c) The angle πΌ1 &lt;=90 degree between πΈβ1 and normal to surface
(d) Normal component of π·2
(e) Tangential component of π·2
(f) Polarization in ππ2 material
(g) The angle πΌ2 between πΈβ2 and normal to surface.
2. A circular line charge of density ππ C/m of radius ‘a’ is lying in XY plane
with its centre at origin. Calculate the potential at point (0,0,h).
3. Three point charges 3C, 4C and 5C are situated in free space at three
corners of an equilateral triangle with side 5cm. Find the energy density
due to electric field in the triangle.
4. A dielectric sphere of radius ‘b’ and permittivity ‘π’ is situated in vaccum.
It is charged throughout its volume by a charge density ππ£ = 5 π⁄π , ‘r’
being the distance from the centre of sphere. Determine the
electrostatic energy of the system.
Compiled by: Parul Dawar, Inderpreet Kaur, Gunjeet Kaur
GURU TEGH BAHADUR INSTITUTE OF TECHNOLOGY
5. For the configuration of figure, find V and E for π &lt; π &lt; πΌ using
Laplace’s equation. Hence find the capacitance of the system.
6. Find the potential that give rise to πΈβ = 2π₯π¦ π₯Μ+π₯ 2 π¦Μ-π§Μ .
7. Given cylindrical electric fields
Find the potential difference ππ΄π΅ for A(1,0,0) and B(4,0,0).
8. Given a field
Calculate ππ΄π΅ for A(-5,2,1) and B(6,1,2).
9. Calculate the field due to a line charge considering it a special Gaussian
surface. (keep it along z-axis)
10. A circular disk r&lt;= 2m, in the z =0 plane has a charge density ρs = 10-8
c/ m2. Determine the electric field πΈβ at (0, Ο, h) .
11.Calculate the capacitance between concentric metal spheres of radius π1
and π2 with charge Q placed at the outer surface of inner shell.
12.State and derive the Pointing Theorem.
13.Explain briefly the term Polarisation.
14.Current density in a certain region is given by
(a) Find the total current crossing the surface z=3, r&lt;6, in π§Μ direction.
(b) Find
πππ£
ππ‘
Compiled by: Parul Dawar, Inderpreet Kaur, Gunjeet Kaur
GURU TEGH BAHADUR INSTITUTE OF TECHNOLOGY
(c) Calculate the total current crossing the closed surface bounded by z=0,
z=3, r=1, r=6.
(d) Is
?
15.A current of 25A passes down z-axis, enters a thin shell of radius 6cm
and π =
π
2
enters a plane sheet as in figure. Write expressions for the
current densities in spherical shell and in plane.
16.The potential field at any point in a space containing a dielectric material
of relative permittivity 2.1 is given by
Where x,y,z are in meters. Calculate the volume charge density at point
P(2,5,3).
17.A charge distribution with spherical symmetry has volume charge
density
Calculate:
(a) The electric field intensity at all the points
(b) Potential at all the points
(c) Total energy stored in electrostatic field.
18.Given a current density
Compiled by: Parul Dawar, Inderpreet Kaur, Gunjeet Kaur
GURU TEGH BAHADUR INSTITUTE OF TECHNOLOGY
π
in spherical coordinates. Find the current crossing the conical strip, π = ,
4
0.001≤r≤0.080m.
19.Find the potential and electric field intensity for region between two
concentric right circular cylinders, where v=0 at ππ =1mm and V=100V at
ππ =20mm. Neglect the fringing.
20.A point charge π1 =300ππΆ located at (1,-1,-3)m experiences a force
due to a point charge π2 at (3,-3,-2)m. Determine π2 .
Compiled by: Parul Dawar, Inderpreet Kaur, Gunjeet Kaur
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