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DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper1 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper1 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time:
3 hours 
Max. Marks: 75

PART
A (25 Marks) 

1. a. State and Express the Coulomb‟s Law.

(2M)

b. Derive the Possion‟s and Laplace Equations for electrostaticfield.

(3M)

c. State and Express the BiotSavart‟s Law.

(2M)

d. Writedown the Maxwell‟s Equations in word statement.

(3M)

e. Define the Uniform Plane wave.

(2M)

f .Define the Surface Impedance.

(3M)

g.Define the characterstic impedance.

(2 M)

h. Define the phase velocity.

(3 M)

i. Define the Reflection Coefficient

(2 M)

j. Explain the losses in transmission Line.

(3 M)

PARTB (5*10=50
Marks)
Marks)
2. a. State and Prove Gauss‟s Law.
b.Let = 400Sinθ/(r^{2}+4) a_{r} A/m^{2}.
Find the total current flowing through that portion of the
b.Let = 400Sinθ/(r^{2}+4) a_{r} A/m^{2}.
Find the total current flowing through that portion of the
spherical
surface r=0.8 bounded by 0.1<θ<0.3π ,0<<2π.
surface r=0.8 bounded by 0.1<θ<0.3π ,0<<2π.
OR
3.a. Show That = ρ
b.Given The Flux density D=16/r cos(2θ) c/m^{2},
Find the total charge with in the region 1<r<2m, 1<
θ<2rad,1< <2π
Find the total charge with in the region 1<r<2m, 1<
θ<2rad,1< <2π
4.
a.State The Law required to calculate magnetic flux density or magentic field
intensity for a given
current or current distribution and derive the expression for the same.
a.State The Law required to calculate magnetic flux density or magentic field
intensity for a given
current or current distribution and derive the expression for the same.
b.Derive the conditions at boundary
surface of DielectricDielectric interface?
surface of DielectricDielectric interface?
OR
5.a. Define and Explain Ampere‟s circuit Law.
b.State Maxwell‟s Equations in Differential and Integral form with clear statement
6.
a. Derive the equation
for uniform plane wave in terms of H.
a. Derive the equation
for uniform plane wave in terms of H.
b. A
100MHz uniform plane wave Propagates in a lossless medium for which _{r}=5
and µ_{r}=1
find v_{p},β,λ,E_{s,}H_{s.}
100MHz uniform plane wave Propagates in a lossless medium for which _{r}=5
and µ_{r}=1
find v_{p},β,λ,E_{s,}H_{s.}
OR
7. a. State and Prove the Pointing Theorem
b. Write short Notes on
b. Write short Notes on
i)Surface impedance ii) Brewster Angle
8.
a. Derive The Expression
for Transmission Line Equation. b. Given R = 10.4
Ω/mt
a. Derive The Expression
for Transmission Line Equation. b. Given R = 10.4
Ω/mt
L
= 0.00367 H/mt
= 0.00367 H/mt
G
= 0.8×10^{4}
mhos/mt
= 0.8×10^{4}
mhos/mt
C
= 0.00835 µF/mt.
= 0.00835 µF/mt.
Calculate
Z_{0}
and at 1.0
KHz.
Z_{0}
and at 1.0
KHz.
OR
9.Derive the expression
for α and β in terms of primary constants of a line
for α and β in terms of primary constants of a line
10.a) Establish the relations for Z_{sc} and Z_{oc} of rf lines and sketch their variation with
βl
βl
b) A 60ohm lossless line
is 30m long and is terminated with a load of 75+j50ohms at 3MHz
is 30m long and is terminated with a load of 75+j50ohms at 3MHz
find its
reflection coefficient,VSWR,if the line velocity is 60% of the velocity of
light
reflection coefficient,VSWR,if the line velocity is 60% of the velocity of
light
OR
11. a) Explain the principle of single
stub matching. b)Calculate the skin depth for the following conditions.
stub matching. b)Calculate the skin depth for the following conditions.
i) Copper f=10^{10}Hz,µ=µ_{0},
σ=5.8×10^{7}s/m
σ=5.8×10^{7}s/m
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DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper2 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper2 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time:
3 hours 
Max. Marks: 75


PART
A (25 Marks) 

1. a.
Define Electric Potential and Ploarization 
(2M)


b. Define
Capacitance? Explain different types of capacitances 
(3M)


c.
State and Express the Amperes circuit Law 
(2M)


d. Define the
boundary condition? Give the relations for electric field 
(3M)


e. Define
Brewster Angle 
(2M)


f. Define
Polarization? Explain different types of polarization 
(3M)


g. Define the
Propagation constant in terms of primary constants 
(2M)


h. Define the
group velocity 
(3M)


i. Define the
stub? 
(2M)


j. Write down
the Applications of Smith chart 
(3M)


PARTB (5*10=50 Marks)


2.a.
State 
and prove the
coulomb‟s law ? 
b. Find
the force on a charge of 100mC located at P(2,0,5) in free space due to
another charge 300µC located at Q(1,2,3).
the force on a charge of 100mC located at P(2,0,5) in free space due to
another charge 300µC located at Q(1,2,3).
OR
3. a. State and
Prove Laplace‟s and Poissson‟s Equation Starting from
Gauss‟s Law
Prove Laplace‟s and Poissson‟s Equation Starting from
Gauss‟s Law
b. The potential
field V=2x^{2}yzy^{3}z
exists in a dielectric medium having ε=2ε_{0} calculate
field V=2x^{2}yzy^{3}z
exists in a dielectric medium having ε=2ε_{0} calculate
. the
total charge within the unit cube 0<x<1m,0<y<1,0<z<1m.
total charge within the unit cube 0<x<1m,0<y<1,0<z<1m.
4.a. Define Ampere‟s Circuit Law in point
and integral forms for Static fields.
and integral forms for Static fields.
b.
Establish the fields in the different regions of a coaxial cable carrying a
current I, and sketch their variation with radial distance.
Establish the fields in the different regions of a coaxial cable carrying a
current I, and sketch their variation with radial distance.
OR
5. a.State and Prove Boundary condition between DielectricDielectric
b. A Potential field is given by V=15(x^{2}y^{2}).The
point p(4,2,1) lies on the boundary of the conductor and free space At P,
obtain the magnitudes of i) V ii) E iii) E_{N}
iv) E_{tan}
v)D vi) ρ_{s}
point p(4,2,1) lies on the boundary of the conductor and free space At P,
obtain the magnitudes of i) V ii) E iii) E_{N}
iv) E_{tan}
v)D vi) ρ_{s}
6. a. Derive The
attenuation and phase constant in conducting medium
attenuation and phase constant in conducting medium
b. At 50MHz, a lossy dielectric
material is characterized by ε=3.6ε_{0}, µ=2.1µ_{0} and σ=0.08S/m. If
Es=6e^{ϒx}azV/m, compute i) ϒ ii) λ iii) u
iv)η v) H_{S}
material is characterized by ε=3.6ε_{0}, µ=2.1µ_{0} and σ=0.08S/m. If
Es=6e^{ϒx}azV/m, compute i) ϒ ii) λ iii) u
iv)η v) H_{S}
OR
7. a.Derive Expression for reflection and transmission coefficients of an EM wave
when it is incident normally on a dielectric
when it is incident normally on a dielectric
b. A perpendicularly polarized wave is
incident at an angle of ө_{i}=15degrees.
It is propagating from medium1 to medium2 .medium 1 is defined by ε_{r1}=8.5,μ_{r1}=1,σ_{1}=0
and medium 2 is free space if E_{i}=1mv/m,
determine E_{r},
H_{i},
H_{r}
incident at an angle of ө_{i}=15degrees.
It is propagating from medium1 to medium2 .medium 1 is defined by ε_{r1}=8.5,μ_{r1}=1,σ_{1}=0
and medium 2 is free space if E_{i}=1mv/m,
determine E_{r},
H_{i},
H_{r}
8. a. Derive The Condition
for Distrotionless Transmission Line
for Distrotionless Transmission Line
b. Measurements on a Transmission Line
of length 120Km were made at frequency of 6000Hz.If Z_{OC}=520(30deg)
and Z_{SC}=640(43deg)
find Z_{o}
and P.
of length 120Km were made at frequency of 6000Hz.If Z_{OC}=520(30deg)
and Z_{SC}=640(43deg)
find Z_{o}
and P.
OR
9. a. Derive The Basic
Transmission Line Equation
Transmission Line Equation
b.The propagation constant of a lossy transmission line is 1+j2 m^{1} and its
characteristic impedance is
characteristic impedance is
20+j0Ω
at ω= 1rad/s. Find R,C,L,G for the Line.
at ω= 1rad/s. Find R,C,L,G for the Line.
10.a.Derive the relation between reflection coefficient and characteristic impedance
b. Write short notes on smith chart
b. Write short notes on smith chart
OR
11.A transmission line of
length 0.40λ ? has a characteristic impedance of 100Ω and is Terminated in a
load impedance of 200 + j180ω. Find the
length 0.40λ ? has a characteristic impedance of 100Ω and is Terminated in a
load impedance of 200 + j180ω. Find the
(a) Voltage
reflection coefficient
reflection coefficient
(b) Voltage
standing wave ratio
standing wave ratio
(c) Input
impedance of the line.
impedance of the line.
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper3 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper3 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time:
3 hours 
Max. Marks: 75


PART
A (25 Marks) 

1.a.Define
Electric field and 
Electric flux
Density 
(2M)

b. Define
Electric dipole? Differentiate between polar and non polar dielectrics 
(3M)


c. State and
Express the Stokes Theorem 
(2M)


d. Write down
the Maxwell‟s equations in free space condition 
(3M)


e. Define Skin
depth or Depth of penetration 
(2M)


f. State and
Express the Poynting theorem 
(3M)


g. Write down
the Distortionless Line 
(2M)


h. Define
Transmission line? Explain different types of Transmission lines 
(3M)


i. Define the
voltage Standing Wave Ratio 
(2M)


j. Difference
between the single stub matching and double stub matching 
(3M)


PARTB
(5*10=50 Marks) 

2. a. Define
Line charge Density? Derive the infinite line Electric field E=ρ_{L}/2 
a_{ρ}


b. Find E
at(2,0,2) if a line charge of 10PC/m lies along the yaxis 

OR

3. a.
Define Capacitance and obtain the parallel plate capacitance
Define Capacitance and obtain the parallel plate capacitance
b. A parallel plate capacitance has 500mm side plates of square shape separated by
10mm distance A sulphur
slab of 6mm plates with ε_{r}=4
kept is on the lower plate find the capacitance of the set up If a voltage of
100V is applied across the
slab of 6mm plates with ε_{r}=4
kept is on the lower plate find the capacitance of the set up If a voltage of
100V is applied across the
capacitor calculate the voltages at both
the regions of the capacitor between the plates.
the regions of the capacitor between the plates.
4 .a. Derive an expression for magnetic
field strength,H,due to a finite filamentary conductor carrying a current I and
placed along Zaxis at a point „P‟ on Yaxis. Hence deduce the magnetic field
sgtrength for the length of the conductor extending ∞ to +∞.
field strength,H,due to a finite filamentary conductor carrying a current I and
placed along Zaxis at a point „P‟ on Yaxis. Hence deduce the magnetic field
sgtrength for the length of the conductor extending ∞ to +∞.
b. State and
Prove BiotSavart‟s Law.
Prove BiotSavart‟s Law.
OR
5.a.What is the inconsistency of Ampere‟s Law
b.A certain material has σ=0 and ε_{r}=1 if H=4sin(10^{6}t0.01z) A/m.
Make use of Maxwell‟s equations to find µ_{r}.
Make use of Maxwell‟s equations to find µ_{r}.
6. a. Show that E and H are
perpendicular to each other inphase and the ratio of their Magnitudes is a
constant for a uniform plane wave.
perpendicular to each other inphase and the ratio of their Magnitudes is a
constant for a uniform plane wave.
b.
A uniform plane wave at
a frequency of 1GHz is travelling in a large block of teflon
A uniform plane wave at
a frequency of 1GHz is travelling in a large block of teflon
ε_{r}=2.1,µ_{r}=1
andσ=0. Determine ϒ,η,β,λ.
andσ=0. Determine ϒ,η,β,λ.
OR
7. a.Define Polyting’s theorem and Polyting Vector.
b. A Sinsoidally varying EM wave in a medium of ε_{r}=1
µ_{r}=1
is transmitting power at a density 1.2watts/m^{2}
.Find the maximum values of E and H fields.
µ_{r}=1
is transmitting power at a density 1.2watts/m^{2}
.Find the maximum values of E and H fields.
8.Explain the
conditions which are used for minimum attenuation in transmission lines
conditions which are used for minimum attenuation in transmission lines
OR
10.a. Derive the expression for the
input impedance of a transmission line of length L. b. List out the
applications of transmission lines
input impedance of a transmission line of length L. b. List out the
applications of transmission lines
OR
11
.Describe the construction of smith chart and give its applications.
.Describe the construction of smith chart and give its applications.
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DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper4 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper4 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time:
3 hours 
Max. Marks: 75

PART
A (25 Marks) 

1.a.
State and Express the Divergence theorem 
(2M)

b. A charge of
10PC is at rest in free space.Find the potential at a point, 

A 10cm away
from the charge. 
(3M)

c. A magnetic
field, H=3a_{x}+2a_{y},A/m exists at a point in free space, what is the 

magnetic flux
density at the point 
(2M)

d. Explain the
different types of medium 
(3M)

e. Define the
Good Conductor 
(2M)

f.Differences
between intrinisic impedance and surface impedance 
(3M)

g. Define the characterstic
impedance in terms of the open circuit and short circuit 

impedance

(2M)

h. Define and
Explain the infinite Line 
(3M)

i. Define the
smith chart 
(2M)

j. Write downthe relation between reflection coefficient and voltage standing wave


ratio

(3M)

PARTB
(5*10=50 Marks) 
2.a .State coulomb‟s and derive the
expression for coulomb‟s law to calculate the magnitude of The force between
two charges
expression for coulomb‟s law to calculate the magnitude of The force between
two charges
b.Prove the poisson‟s equation for Electrostatic field
OR
3.a.Distinguish between the conduction
and convention currents. Establish the current Continuity equation and hence
calculate the relaxation time for brass material, having Conductivity of 1.1×10^{7}mho/m
at 10MHz.
and convention currents. Establish the current Continuity equation and hence
calculate the relaxation time for brass material, having Conductivity of 1.1×10^{7}mho/m
at 10MHz.
b.Find the capacitance of a 50cm.long
coaxial cable, having conductors of 4cm and 2cm diameters, separated by a
medium of a relative permittivity 2.56.
coaxial cable, having conductors of 4cm and 2cm diameters, separated by a
medium of a relative permittivity 2.56.
4.a.Define Inductance? Derive the toroid inductance
b.A toroid has air core and has a
crosssectional area of 10mm^{2}.It
has 1000turns and its mean radius is 10mm.Find its Inductance
crosssectional area of 10mm^{2}.It
has 1000turns and its mean radius is 10mm.Find its Inductance
OR
5.a.Obtain the integral form of Maxwell‟s equation from Amperes circuit law in the
generalized form
b. In a medium of µ_{r}=2,
find E,B and displacement current density if H=25sin(2×10^{8}t+6x)
mA/m
find E,B and displacement current density if H=25sin(2×10^{8}t+6x)
mA/m
6. a.For good dielectrics derive the expressions for α,β,ϒ,η
b. A plane wavetravelling in a medium of ε_{r}=1,µ_{r}=1
has an electric field intensity of
has an electric field intensity of
v/m.Determine the energy density in the
magnetic field and also the total energy density.
magnetic field and also the total energy density.
OR
7.a Derive Expression for
reflection and transmission coefficients of an EM wave when it is incident
normally
on a dielectric.
reflection and transmission coefficients of an EM wave when it is incident
normally
on a dielectric.
b.A perpendicularly polarized wave is incident at an angle of ө_{i}=15degrees.
It is is free propagating from medium1 to medium2 .medium 1 is defined by
ε_{r1}=8.5,μ_{r1}=1,σ_{1}=0 and medium2 space if E_{i}=1mv/m, determine E_{r}, H_{i},
H_{r.}
It is is free propagating from medium1 to medium2 .medium 1 is defined by
ε_{r1}=8.5,μ_{r1}=1,σ_{1}=0 and medium2 space if E_{i}=1mv/m, determine E_{r}, H_{i},
H_{r.}
8.a.Derive the attenuation constant and
phase constant in terms of primary constants b.Explain different types of
loading for transmission lines.
phase constant in terms of primary constants b.Explain different types of
loading for transmission lines.
OR
9.a.Derive the characteristic impedanceof a transmission line in terms of its line constants
b.At 8MHz thecharacteristic impedance of a transmission line as 40j2ohms and the
b.At 8MHz thecharacteristic impedance of a transmission line as 40j2ohms and the
propagation
constant 0.01+j0.18 per meter.Find the primary constant.
constant 0.01+j0.18 per meter.Find the primary constant.
10.Explain the principal of single stub matching
OR
11. a.Derive the relation between reflection coefficient and characteristic impedance
b. write short notes on smith chart.
b. write short notes on smith chart.
jntumaterials.com
DEPARTMENT OF
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper5 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
ELECTRONICS AND COMMUNICATION ENGINEERING B.Tech II year – II Semester
Examinations, Model Paper5 ELECTROMAGNETIC WAVES AND TRANSMISSION LINES
Time:
3 hours Max.
Marks: 75
3 hours Max.
Marks: 75
PART
A (25 Marks) 

1.a.The force F=2a_{x}+a_{y}+a_{z} N, is acting on a charge of 10C, find the electric field


Intensity,its
magnitude and direction. 
(2M)

b.The current density J=1/r^{2}(cosӨa_{r}+sinӨ ),A/m^{2},
find the current passing 

through a sphere radius of 1m

(3M)

c.Given magnetic flux density,B=ρ ,find the total flux crossing the surface


1<ρ<2m and 0<z<5m.

(2M)

d. Define Current? Explain different types of Current Density

(3M)

e. Define The Good dielectric

(2M)

f. Define Skin Depth

(3M)

g. Define the Loading of Line

(2M)

h. Define and Explain infinite line

(3M)

i. Define the Stub

(2M)

j. Define the reflection coefficient and standing wave ratio

(3M)

PARTB (5*10=50
Marks)
Marks)
2.a.State and Explain Coulomb‟s law.
b.Three point charges Q1=0.5nC,Q2=0.4nC, Q3=0.6Nc are located in free space
at(0,0),(3,0)and(0,4)respectively.Determine the potential,electricfield
intensity and flux density at (3,4).
at(0,0),(3,0)and(0,4)respectively.Determine the potential,electricfield
intensity and flux density at (3,4).
OR
3. a.
Determine the amount of work necessary to assemble three point charges Q1,
Q2,Q3 in an empty space. Extend your result to npoint charges.
Determine the amount of work necessary to assemble three point charges Q1,
Q2,Q3 in an empty space. Extend your result to npoint charges.
b. Show that = ρ .
4.
a. State and Prove the Ampere‟s Force Law.
a. State and Prove the Ampere‟s Force Law.
b.A toroidal ring has 200turns. The outer diameter of the ring is 15cm with the
inner diameter of 12cm.Find the flux density if the current is 8A.
inner diameter of 12cm.Find the flux density if the current is 8A.
5.
a. State and explain boundary conditions between two dielectric media.
a. State and explain boundary conditions between two dielectric media.
b. A circular loop conductor having radius of 0.2m is placed in XY plane. The loop
consists of a resistance of 10ohms. If the Magnetic field is B=Sin10^{4}t
consists of a resistance of 10ohms. If the Magnetic field is B=Sin10^{4}t
Tesla, find the current flowing in the loop.
6. a.Discuss the significance of pointing theorem and derive the equation for pointing Vector.
b.A vertically polarized uniform plane wave is incident at an angle of 45^{0}
from air on a dielectric slab of ϵ_{r}=4,µ_{r}=1 and σ=0.the incident field strength is 100mV/m at 10MHz.Calculate the power transmitted to the dielectric slab Find the angle of incidence for which angle of reflection is zero.
from air on a dielectric slab of ϵ_{r}=4,µ_{r}=1 and σ=0.the incident field strength is 100mV/m at 10MHz.Calculate the power transmitted to the dielectric slab Find the angle of incidence for which angle of reflection is zero.
OR
7.a.Derive the equation for uniform plane wave in free space condition.
b.The electric field in free space is given by E=50cos(10^{8}t+βx)a_{y}V/m.Find
the direction of wave propagation.Calculate β and time it takes to travel a
distance of λ/2
the direction of wave propagation.Calculate β and time it takes to travel a
distance of λ/2
8. Derive the equation for input
impedance of the EighthWave(λ/8) line? Explain Its significance
impedance of the EighthWave(λ/8) line? Explain Its significance
OR
9.
Write Short notes on
Write Short notes on
i) Smith
Chart
Chart
ii)Single stub matching
10.a.Derive an expression for thepropagation constant and characteristic impedance of Transmission line withR,L,C,G.
b. A telephone line has
R=30Ω/km, L=100Mh/km, G=0,C=20µF/km. At f=1KHz,obtain i) Z_{0}
R=30Ω/km, L=100Mh/km, G=0,C=20µF/km. At f=1KHz,obtain i) Z_{0}
ii) propagation constant iii ) phase velocity
OR
11.a. Derive an expression for the input impedance of a lossless line of length „l‟
in Terms of Z_{0,} β,Z_{L }and l when terminated by a Z_{L }load.
in Terms of Z_{0,} β,Z_{L }and l when terminated by a Z_{L }load.
b. A lossless transmission line length
„l‟ with Z_{0}=50
is terminated by a load of Z_{L}=50+j50.Determine
the reflection coefficient “R_{r}”
and the standing wave
„l‟ with Z_{0}=50
is terminated by a load of Z_{L}=50+j50.Determine
the reflection coefficient “R_{r}”
and the standing wave
Ratio.
.
Tags: Electromagnetic Theory and Transmission Lines Important Questions JNTUH R13