Download PTU B.Tech 2021 Jan EEE 3rd Sem 76466 Electromagnetic Fields Question Paper

Download PTU (Punjab Technical University) B.Tech (Bachelor of Technology) / BE (Bachelor of Engineering) 2021 January EEE 3rd Sem 76466 Electromagnetic Fields Previous Question Paper

Roll No.
Total No. of Pages : 02
Total No. of Questions : 18
B.Tech. (Electrical & Electronics Engg./Electronics & Electrical Engg.)
(2018 Batch) (Sem.?3)
ELECTROMAGNETIC FIELDS
Subject Code : BTEEE-304-18
M.Code : 76466
Time : 3 Hrs. Max. Marks : 60
INST RUCT IONS T O CANDIDAT ES :
1 .
SECT ION-A is COMPULSORY cons is ting of TEN questions carrying TWO marks
each.
2 .
SECT ION-B c ontains F IVE questions c arrying FIVE marks eac h and s tud ents
have to atte mpt any FOUR q ues tions.
3 .
SECT ION-C contains THREE questions carrying T EN marks e ach and s tudents
have to atte mpt any T WO questio ns.
SECTION-A
1.
State divergence theorem.
2.
Distinguish between transformer and motional emf.
3.
Derive the expression for divergence of a vector field in cylindrical coordinate system.
4.
Explain skin depth.
5.
If A 2 a 4
x
a y and B 6 a 4
y
a z . Find the smaller angle between them using cross
product. Verify it using dot product.
6.
Find D at P (6, 8 ? 10) due to a point charge of 50 mC at origin.
7.
State the significance of displacement current in the context of Maxwell's equations.
8.
Calculate the Poynting vector at the surface of a cylindrical conductor of radius `a' and
conductivity carrying a steady current I distributed uniformly over its cross section.
9.
Deduce Coulomb's law from Gauss's law.
2
x
10.
Transform A y a x x a y
az to cylindrical coordinates.
2
2
x y
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SECTION-B
11. If the two vectors are represented by :
A 5 a 2
r
a a
B a 3 a0 4
r
a
Find :
I.
A B
II. Angle between A and B
III. Unit vector normal to the plane containing both A and B
IV. Vector projection of A on B .
12. Prove the vector identity :
2
A (. A ) A.
13. State the necessity of magnetic vector potential for magneto-static fields.
14. Use Laplace equation to obtain the capacitance for a coaxial capacitor. Assume suitable
coordinate system and boundary values.
15. A wire in the form of a parabola carries current 3A. Calculate the magnitude of the
magnetic field intensity at its focus if the distance from the focus to the apex (or vertex)
is 20 cm.
SECTION-C
16. Derive both differential and integral forms of Ampere's Circuital Law for time-varying
and time-harmonic fields.
17. Derive the expressions for and for a lossy dielectric medium.
18. A non-magnetic medium has an intrinsic impedance of 24030?. Find ?
I. Loss tangent
II. Dielectric constant
III. Complex permittivity
IV. Attenuation constant at 1 MHz.
NOTE : Disclosure of Identity by writing Mobile No. or Making of passing request on any
page of Answer Sheet will lead to UMC against the Student.
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