Download AKTU B-Tech 4th Sem 2016-17 NEC404 Electromagnetic Field Theory Question Paper

Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU) B-Tech 4th Semester (Fourth Semester) 2016-17 NEC404 Electromagnetic Field Theory Question Paper

Printed Pageszl RollN0.I I I I I I I I I I I NEC404
B. TECH.
THEORY EXAMINATION (SEM?IV) 2016-17
ELECTROMAGNETIC FIELD THEORY
T ime : 3 Hours Max. Marks : 100
Note : Be precise in your answer. In case ofnumerical problem assume data wherever not provided.
SECTION ? A
1. Attempt all parts of the following questions: 10 x 2 = 20
(a) Explain the physical significance of Divergence and Curl.
(b) Derive and expression for inductance per unit length of coaxial conductors.
(c) Express B = (170) r + 7' cos 9 9 in cylindrical coordinates.
(d) Explain the terms ? Transmission coef?cient and re?ection coefficient.
(e) Prove the electric field vector E = (grad V), where V is a scalar potential field.
(1) Transform the point (1, 1, 6) to spherical coordinates.
(g) Verify whether the scalar field 5 = pzzc052d) d) in cylindrical coordinates in a
solution of Laplace?s equation.
(h) A copper wire carries a conduction current of 1 amp at 60 Hz. What is the displacement
current in the wirte? Assume ,u = ,uo, 5 = 50 and c7 = 5.8 X 107 ohm/m.
(i) State Stroke?s theorem and Divergence theorem.
(j) State the Gauss?s law and derive the related Maxwell equation.
SECTION ? B
2. Attempt any ?ve of the following questions: 5 x 10 = 50
(a) Derive and explain the mathematical form of Poynting theorem.
(b) Given that D = (52?2)?? in spherical co?ordinate. Find the volume enclosed between
r=1and r=2.
(c) Explain the phenomenon of polarization and its types.
(d) Prove that the magnetic field due to an infinite conductor carrying current i at a
distance r is H = ; A/m
an
(e) Explain the tangential and normal boundary conditions between two dielectrics for
static electric fields.
(1) Calculate E at P(l, 1, 1) in free space caused by four identical 3-nC point charges
located atp1=(1, 1,0), p2 = (-1, 1, 0), p3 = (-1, ?1,0) and p4 = (1, -1, 0).
(g) State and explain Maxwell?s equations for time varying fields in differential and
integral forms and their significance.
(h) A uniform plane wave propagating in good conductor. If the magnetic field intensity is
given by H = 0.16?15 cos(27r x 1081 ? 15z)i A/m, determine the conductivity and
corresponding component of E field. Also calculate the average power loss in a block
of unit area and thickness t.
SECTION ? C
Attempt any two of the following questions: 2 x 15 = 30
3 A uniform plane wave propagating in a medium has E = 2e_?z sin(108t ? ,Bz) j V/m.
If a medium is characterized by er = 1, ,ur = 20 and c = 3 S/m, determine a, B and H.
4 Discuss the solution of plane wave equation in conducting media (Lossy Dielectric).
Derive the above up to Propagation Constant. Attenuation Constant and Phase
Constant.
5 Explain the re?ection of plane wave for the normal incidence. Discuss about Re?ection
and Transmission coefficient for F and H.