B.Tech. DEGREE EXAMINATION, MAY - 2013 … · · 2014-02-03... Write the form of Fourier series for f (x) in the interval 0 < x < 2π. e) ... 4 3, if 2 1 < x < 1, as the Fourier

��Total No. of Questions : 5] [Total No. of Pages : 03

B.Tech. DEGREE EXAMINATION, MAY - 2013(Examination at the end of Second Year)

ELECTRONICS AND COMMUNICATIONS(Paper - I) : Mathematics - III

Time : 03 Hours Maximum Marks : 75

Answer Question No.1 compulsory (15 × 1 = 15)

Answer ONE question from each unit (4 × 15 = 60)

Q1) a) Define even function.

b) Define periodic function.

c) If f (x) = x2 in the interval (–l, l), then find the Fourier coefficient a0.

d) Write the form of Fourier series for f (x) in the interval 0 < x < 2π.

e) State Fourier integral theorem.

f) State modulation theorem of Fourier transform.

g) Write any two properties of Fourier transform.

h) Show that 1 – ∇ = E–1.

i) Define the shift operator E.

j) Define interpolation.

k) Write Newton’s forward interpolation formula.

l) Write the Lagrange’s interpolation formula.

m) Define numerical integration.

n) State Trapezoidal rule.

o) State Simpson’s 1

3 rule.

UNIT - I

Q2) a) Obtain the Fourier series for f (x) = e–x in the interval 0 < x < 2π.

b) Expand f (x) = 4

1 – x, if 0 < x <

2

1

= x – 4

3, if

2

1 < x < 1,

as the Fourier series of sine terms.

OR

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c) Obtain Fourier series for the function f (x) given by

f (x) = 1 + 2x/π, –π < x < 0,

= 1 – 2x/π, 0 < x < π.

Deduce that 2

2 2 21 1 1

...81 3 5

+ + + = .

d) Find the complex form of Fourier series of the function f (x) = cos ax in the interval–π < x � π.

UNIT - II

Q3) a) Find the Fourier transform of e–a2x2, a > 0. Hence show that the function of

2

2x

e−

isself reciprocal.

b) Using Regula-Falsi method, compute the real root of the equation x3 – x – 11 = 0correct to three decimal places.

OR

c) Find the Fourier cosine transform of f (x) = 21

1

x+.

d) Solve the following equations by Gauss elimination method :

2x + y + z = 10; 3x + 2y + 3z = 18; x + 4y + 9z = 16.

UNIT - III

Q4) a) Estimate the values of f (22) and f (42) from the following data :

x : 20 25 30 35 40 45

f(x) : 354 332 291 260 231 204

OR

b) Using Newton’s divided difference formula, evaluate f (8) from the following data :

x : 4 5 7 10 11 13

f (x) : 48 100 294 900 1210 2028

c) Find y' (0) and y" (0) from the following table :

x : 0 1 2 3 4 5

y : 4 8 15 7 6 2

UNIT - IV

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Q5) a) Evaluate 6

20 1

dx

x+∫ by using Simpson’s 3

1 rule.

b) Using Taylor’s series method, compute y (0.2) to three places of decimal from

xydx

dy21−= , given that y(0) = 0.

OR

c) Using Euler’s method solve for y at x = 0.1 from ,1)0(, =++= yxyyxdx

dy taking step

size h = 0.025.d) Apply Runge - Kutta fourth order method to find an approximate value of y when

x = 0.2, given that yxdx

dy+= and y = 1 when x = 0. Take h = 0.2.

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Total No. of Questions : 9] [Total No. of Pages : 02

B.Tech. DEGREE EXAMINATION, MAY - 2013

(Examination at the end of Second Year)

ELECTRONICS & COMMUNICATIONS

(Paper - II) : Circuit Theory


Answer Question No. 1 compulsory. (15 × 1 = 15) Answer ONE question from each unit. (4 × 15 = 60)

Q1) a) Define Energy.b) What is an dependent source?c) Equation for energy stored in inductor.d) Define Tree.e) State reciprocity theorem.f) Define compensation theorem.g) Define crest factor.h) What is meant by RMS value.i) Define power factor.j) Define parallel resonance.k) What is meant by bandwidth.l) State final value theorem.m) Define time constants.n) What is meant by phase sequence.o) Give the equation of power in the star-connected network.

UNIT - IQ2) a) State and explain the kirchoff’s laws.

b) A capacitor is charged to 50 c. The voltage across the capacitor is 150V. It is thenconnected to another capacitor four times the capacitance of the first capacitor. Findthe loss of energy.

ORQ3) a) Explain briefly the method of solving an electrical circuit using supermesh analysis.

b) Write the node voltage equations and determine the currents in each branch for thenetwork shown. in fig.

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UNIT - IIQ4) a) State and explain maximum power transfer theorem.

b) Determine The thevenin’s equivalent circuit across ‘AB’ for the given circuitshown in fig.

OR

Q5) a) Explain the operation of RLC series circuit with respective phasor diagrams and alsoderive required equations.

b) For the resistive network shown in fig. Find the current in each resistor, using thesuperposition principle.

UNIT - IIIQ6) a) For a - connected resistive network. Compute open circuit z-parameters.

b) Consider a R-L-C series network. Derive the resonance condition for such a networkalso derive the bandwidth and Q-factor.

OR

Q7) Determine Va and V

b for the network shown in fig.

UNIT - IV

Q8) a) Give the properties of Laplace transforms.

b) A balanced star connected load of (4 + j3) per phase is connected to balanced 3-phase 400 v supply. The phase current is 12A. Find

(i) Total apparent power (ii) Total active power (iii) reactive power.

ORQ9) a) Explain about the generation of 3-phase voltages.

b) Find the laplace transform of (t + 2)2 et.

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Electronics & Communications

(Paper - III) : ELECTRONIC DEVICES


Answer Question No. 1 compulsory

Answer ONE question from each unit

Q1) a) What is meant by effective mass of electron?

b) State the law of conservation of energy.

c) Define hall effect.

d) Define p & n materials.

e) What is Gunn effect?

f) Define Zener breakdown.

g) What is meant by Diffusion Capacitance?

h) List the applications of LCD.

i) What are applications of CE configuration?

j) Define γβ & of a transistor.

k) Define early effect in a transistor.

l) What is meant by ‘Q’ point in BJT?

m) Why is a FET called so?

n) List the applications of UJT.

o) List the applications of CRO.

UNIT - I

Q2) a) Explain Electrostatic focussing.

b) Explain law of mass action in a SC.

OR

Q3) a) Write short notes on Diffusion and Diffusion length.

b) Explain the motion of charged particles in electric field.

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UNIT - II

Q4) a) Draw the VI characteristics and explain working of a PN junction diode.

b) Explain the working of a photo diode.OR

Q5) a) Explain the function of Zenerdiode as a voltage regulator.

b) Write short notes on temperature dependence of diode.

UNIT - III

Q6) a) Explain Transistor Current Components.b) Write short notes on voltage stabilization.

ORQ7) a) With neat figure explain the working of a photo transistor.

b) Explain how a transistor acts as an amplifier?

UNIT - IV

Q8) a) Draw the Drain and transfer characteristics of FET and explain its working.b) Explain the function of a TRIAC.

ORQ9) a) Discuss the features of P-N-P-N- devices.

b) Explain the function of a Depletion MOSFET.

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(Paper - IV) : EMF Theory


Answer Question No. 1 compulsory (15) Answer One question from each unit (4 × 15 = 60)

Q1) a) What is electric flux. (1)b) List the applications of Poisson’s equation. (2)c) Define a point charge (Q). (1)d) What is the energy stored in electrostatic field. (2)e) What is the Quality factor of a coil. (1)f) Define Biot-Savart’s Law. (2)g) What is meant by magnetic susceptibility. (2)h) Define wavelength of wave (). (1)i) What is meant by intrinsic impedance. (2)j) Define attenuation constant. (1)

UNIT - I

Q2) a) Derive the expression for D due to a point charge using Gauss’s Law.b) Obtain the relation between E and V.

ORQ3) a) State and explain Coulomb’s Law.

b) A sphere whose radius is 0.5m contains a charge density of v = (5 – 2r) c/m3. Find

D at a distance 10m away from the center of sphere.

UNIT - II

Q4) a) Using ampere’s circutal law, find H due to infinite sheet of current.

b) The conducting triangular loop is as shown in fig. carries a current of 10A, find H at(0, 0, 6) due to side 1 of the loop.

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OR

Q5) a) Explain the terms scalar and vector magnetic potential.

b) State and prove Maxwell’s third equation.

UNIT - III

Q6) a) Explain Faraday’s law of electromagnetic induction.

b) Discuss the inconsistency of Ampere’s law.

OR

Q7) a) Explain motional EMF.

b) List the applications of Maxwell’s equations.

UNIT - IV

Q8) a) Explain uniform plane waves propagation.

b) Write short notes on conductors.

OR

Q9) a) Explain the role of reflection and refraction of plane waves.

b) An elliptical polarised wave has an electric field of E = Sin (wt – z) ax + 2 sin

(wt – z +75º) ay V/m. Find the power per unit area conveyed by the wave in free

space.

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ELECTRONICS AND COMMUNICATIONS(Paper - V) : Digital Electronics


Answer question No. 1 compulsory. Answer one question from each unit.

Q1) a) Define a bit. (15 � 1 = 15)

b) How do you convert a Hex number into binary.

c) What do you mean by odd parity?

d) What is the merit of Hamming code?

e) What is a half adder?

f) What is an encoder?

g) What is modular design?

h) Define a flip flop.

i) What is meant by race around condition in flip flops?

j) What is dynamic triggering?

k) Define Hold time of a flip flop.

l) Draw a JK flip flop.

m) List the applications of counters.

n) What are the advantages of TTL gate?

o) What is parallel loading?

UNIT - I

Q2) a) Evaluate (4796)10

= ( )8 = ( )

16 = ( )

2.

b) Define universal gates. Implement EX-OR gate using any one universal gate.

OR

Q3) a) i) Multiply [267�� 5]8.

ii) List the advantages of Alphanumeric Codes.

b) Reduce the function 11,12,14)(2,8,9,10,Mπ=f and implement in NAND logic.

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UNIT - II

Q4) a) With a neat figure explain the function of a comparator.

b) How do you use Hamming code for error detection and correction.OR

Q5) a) Draw the logic diagram and truth table of EX-NOR circuit using universal gates andexplain its function.

b) Design a binary adder.

UNIT - III

Q6) a) Explain the function of a JK flip flop.b) Design a Mod-5 asynchronous counter using flip flop.

ORQ7) a) Draw the truth table and explain the function of Master slave JK flip flop.

b) List the differences between Asynchronous counters and Synchronous counters.

UNIT - IV

Q8) a) Compare DTL and TTL families.b) Explain the features of PLA.

ORQ9) a) Draw a neat figure and explain PAL.

b) List the advantages of CMOS and MOS.

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(Paper - VI) : Data Structures Using C



Q1) a) What is array?

b) What is the significance of linked list?

c) Differentiate double linked list and circular linked list.

d) Define stack.

e) What is Dequeue?

f) What is the purpose of recursion?

g) What do you mean by Hashing?

h) Differentiate tree and Binary tree.

i) Define AVL tree.

j) Define ADT.

k) What do you mean by traversing?

l) Define circular Queue.

m) What do you mean by dynamic allocation?

n) Differentiate tree and graph.

o) What is the significance of Sorting?

UNIT - 1

Q2) Explain various operations on double linked lists and circular linked list.

OR

Q3) Write a C program to insert and delete an element using single linked list and double linkedlists.

UNIT - 2

Q4) Explain the implementation of stack using arrays and linked lists.

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OR

Q5) Explain the implementation of queues using arrays and linked lists.

UNIT - 3

Q6) a) Implement the Quick Sort for the following:69 97 29 8 12 35 47 52 77

b) Write the algorithm for Hesh Sort and Insertion Sorting.

ORQ7) a) Implement Merge Sort for the following:

22 11 44 33 66 55 88 77 99b) Write the algorithm for Radix Sorting and Shell Sorting.

UNIT - 4

Q8) a) Write the algorithm for Binary Search.b) Explain AVL tree with suitable example.

ORQ9) a) Explain about Hashing methods in searching and also discuss its applications.

b) Explain logical operations on trees.

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ELECTRONICS AND COMMUNICATIONS(Paper - I) : Mathematics - IV


Answer Question No.1 compulsory (1 × 15 = 15)Answer any ONE question from each unit (4 × 15 = 60)

Q1) a) Define continuity of f (z).

b) Define Analytic function.

c) State any one property of analytic function.

d) Define harmonic function.

e) State the necessary conditions for f(z) is analytic.

f) State Cauchy’s integral formula.

g) State Taylor’s theorem.

h) Define essential singularity.

i) Define simple pole.

j) Find the poles of zz

zfsincos

1)(

−= .

k) State residue theorem.

l) Write Bessel’s differential equation.

m) Write the expression for P3 (x).

n) Write orthogonal property of legendre polynomial.

o) Write the generating function for Jn (x).

UNIT - I

Q2) a) Find the regular function whose imaginary part is e–x (x cos y + y sin y).

b) Show that the function ( )1 2 2log2

u x y= + is harmonic and determine its conjugate.

OR

Q3) a) If w = log z, find dz

dw and determine where w is non-analytic.

b) State and prove Cauchy-Reimann equations in polar form.

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UNIT - II

Q4) a) State and prove Cauchy’s integral formula.

b) Use Cauchy’s integral formula to evaluate

2

( 1) ( 2)

z

C

edz

z z∫

− −, where C is the circle

|z| = 3.OR

Q5) a) State and prove Taylors series.

b) Find the Laurent’s expansion of )4

2()1

2( +− zz

z for |z| < 1.

UNIT - III

Q6) a) Evaluate 2 2sin ��2( 1) ( 2)C

z zdz

z z∫

− −, where C is the circle |z| = 3.

b) State and prove Residue theorem.

OR

Q7) a) Show that 2

0

2cos 2 d 2 �2 21 2 cos a 1 aa

π θ θ

θ=

− + −∫ (�2 < 1).

b) Solve in series the equation 02

2=++ xy

dx

dy

dx

ydx .

UNIT - IV

Q8) a) Show that Jn (x) = [ ])(1)(1

2xnJxnJ

n

x++− .

b) Show that J–n

(x) = (– 1)n Jn (x).

OR

Q9) a) Show that 1

1

( ) ( ) 0p x p x dxm n−

=∫ , for m ≠ n.

b) Express 5x3 + x in terms of legendre polynomials.

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(Paper - II) : Electronics Circuits - I


Answer Question No. 1 compulsory. (1 × 15 = 15)

Answer ONE question from each unit. (4 × 15 = 60)

Q1) a) Define ripple factor of a rectifier.

b) What are the advantages of Bridge rectifier.

c) Define and of a transistor.

d) What is FET so called.

e) Define ,rd and gm of a JFET.

f) What are half-power frequencies.

g) Define Miller effect.

h) Define time constant ‘’ and risetime ‘tr’ in amplifier.

UNIT - I

Q2) a) How do you obtain the % regulation and ripple factor of a full wave rectifier.

b) Compare the types of filters you use in rectifiers.

OR

Q3) a) Explain the working of a Bridge rectifier with and without filters.

b) How does an inductor act as a filter.

UNIT - II

Q4) a) Explain the method of obtaining ‘h’ parameters from characteristics.

b) Explain with a neat figure ‘T’-mode.OR

Q5) a) Explain the cascode transistor amplifier.

b) How do you measure h-parameters of a BJT.

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UNIT - III

Q6) a) Draw and explain a single stage CE amplifier response.b) Draw the hybrid model of transistor and explain.

ORQ7) a) Determine the input impedance, output impedance Voltage gain and current gain for

CE amplifier shown below. The h-parameters of the transistor are

hfe = 60,

hie = 500 &

Ic = 3 mA

b) Draw the circuit for an emittee follower at high frequencies and explain.

UNIT - IV

Q8) a) What do you mean by cascaded stages. Explain both interacting and Non-interacting.b) Explain the operation of a FET-CS amplifier at high frequencies.

ORQ9) a) What is the effect of bypass capacitor on overall response.

b) Compare CS/CD/CG configurations of FET at low frequencies.

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Electronics & Communications

(Paper - III) : TRANSMISSION LINES & WAVES



Q1) a) Express Attenuation Constant.b) Express propagation constant and characteristic Impedance of a Lossless transmission

line?c) Express Reflection Loss.d) What is meant by Infinite Line?e) Give the Condition for Distortionless Line.f) Find Reflection coefficient for VSWR of 2.g) What is range of reflection coefficient and VSWR?h) Write down an important application of Smith Chart?i) Which is the Dominant TE wave between parallel plates?j) In an Air Line adjacent maxima are found to be 12.5 cm and 37.5 cm. Calculate

Operating frequency?k) What is meant by Degenerate modes?l) Define Q-factor of a Resonator.m) Sketch the excitation of TE

10 mode in a Rectangular wave guide.

n) What is the main difference between Rectangular waveguide and Circular waveguide?o) Which is the dominant mode in circular waveguide?

UNIT - I

Q2) a) Obtain the relationships between Primary and Secondary constants.

b) A telephone line has R = 30Ω /km, L = 100mH/km, G = 0, and C = 20 �� .At f = 1kHz? Obtaini) The characteristic impedance of a line.ii) The propagation constant.iii) The phase velocity.

ORQ3) a) Express wave characteristics of an Infinite Transmission Line?

b) A lossless line has a voltage V(z,t) = V0 sin (wt - � ). Find the corresponding current

wave.

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UNIT - II

Q4) a) Discuss about the parameters of open wire line at high frequencies?

b) A 100 + j150Ω load is connected to a 75Ω lossless line.Find:i) Reflection coefficient.ii) VSWR.iii) Load admittance.iv) Input impedance from the load using smith chart.

ORQ5) a) List out the steps in procedure for solving a double-stub matching problem on the

Smith chart.b) Discuss Input and Output impedance of short circuited lines.

UNIT - III

Q6) a) Derive the expression for attenuation in parallel plane guides.b) Discuss about the field distributions in transverse and longitudinal sections.

ORQ7) a) Does Rectangular waveguide support TM

10 and TM

01 modes. If not so Explain.

b) A rectangular waveguide with dimensions a = 2.5 cm, b = 1cm is to operate below15.1 GHz. How many TE and TM modes can the waveguide transmit if guide is filled

with a medium characterized by 1r,40, 0 === ? Calculate cutoff frequencies of

the modes.UNIT - IV

Q8) a) Discuss about Circular waveguides.b) Sketch and represent Field lines for TM

01 and TE

11 in a transverse plane of circular

waveguide?OR

Q9) a) Discuss about Parallel Transmission Lines. What is its disadvantage, and how this isovercome by Triplate Line?

b) Neglecting losses and fringing effects and assuming the substrate of a stripline to havea thickness 0.4 mm and a dielectric constant 2.25, find

i) The required width of a strip to have Z0 of 50Ω .

ii) Determine L and C of the line.iii) Determine velocity of propagation along the line.

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Paper - IV : Network Analysis & Synthesis


Answer Question No. 1 compulsory. (15 × 1 = 15)

Answer ONE question from each unit. (4 × 15 = 60)

Q1) a) Define shifter functions.b) What are the various unit functions, list out them.c) Define part.d) Which parameters are widely used in transmission line theory.e) List out the properties of symmetrical networks.f) Define crystal filters.g) What is meant by band pass filters.h) Classify the types of filters.i) Define attenuator.j) What is meant by constant resistance equalizer.k) Define equalizer.l) What are positive real functions.m) Define two part functions.n) What is minimum phase network.o) What is the significance of elements in the foster form.

UNIT - I

Q2) a) Explain hybrid parameters in two part network analysis.

b) Classify how many types of network are present in two part network analysis.

OR

Q3) Find the y-parameters for the network shown in below.

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UNIT - II

Q4) a) What are the properties of filter.

b) What is the concept of working of low pass and high pass filters using reactive elements.OR

Q5) Design a T and section constant-k high pass filter having cut-off frequency of 12KHZ andnominal impedance Ro = 500 W. Also Find : (i) Its characteristic impedance and phaseconstant at 24KHZ and (ii) attenuation at 4KHZ.

UNIT - III

Q6) a) Explain Lattiee equalizer with a neat sketch.

b) Explain the equalizer configuration briefly.

OR

Q7) a) Explain Bridged T attenuator with a neat sketch.

b) Explain symmetrical and Asymmetrical attenuators.

UNIT - IV

Q8) a) Explain Foster’s canonic form.

b) Find the second foster form of the admittance function.

2

2 2

s(s + 9)y(s) =

10 (s + 4)(s + 25)

ORQ9) a) Explain cauer form of reactive networks.

b) A driving point of impedance is given by

2 2

LC 2 2

s(s + 4) (s + 6)Z (s) =

(s + 1) (s + 5)

obtain the first form of cauer network.

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(Paper - V) : Electrical Technology


Answer Question No. 1 compulsory

Answer One question from each unit

Q1) a) State Faraday’s laws of Electromagnetic Induction.

b) Define excitation.

c) What is Residual Magnetism?

d) Give the applications of DC Motor.

e) What is Mutual Induction?

f) Draw the circuit diagram of Compound Motor.

g) What is the purpose of starter in a DC Motor?

h) Define slip.

i) What are the losses observed in a transformer?

j) Write the applications of φ−1 induction motors.

k) Draw the equivalent circuit of a transformer.

l) Distinguish between salient pole and cylindrical pole type in alternators.

m) What are the applications of synchronous motors?

n) Define voltage regulation of a transformer.

o) State Lenz’s law.

UNIT - I

Q2) a) Discuss in detail the constructional features of a DC machine.

b) A 6-pole DC machine has an armature with 90 slots and 8 conductors per slot andruns at 1000 rpm, the flux per pole is 0.05 wb. Determine the induced emf if it is

i) Wave Wound.

ii) Lap Wound.

OR

Q3) a) Explain the Swinburne’s test employed for DC machine in detail.

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b) A 25kW, 250V dc shunt generator has armature and field resistances of 0.06 Ω and

100 Ω respectively. Determine the total armature power developed when working

i) as generator delivering 25kW output.

ii) as a motor taking 25 kW input.

UNIT - II

Q4) a) Explain the operation of a transformer under loaded conditions. Also represent suchcases by considering R,L,C type of loads.

b) Discuss about the short-circuit test conducted on a transformer.

OR

Q5) a) What is an Auto-transformer? Explain the theory and application of such a machine.

b) Explain about the Delta/star connected transformer with phasor diagrams.

UNIT - III

Q6) a) Derive various torques developed in a 3-phase induction motor.

b) Distinguish between φ−1 and φ−3 induction motors.

OR

Q7) a) Describe briefly the constructional features of 3-phase induction motor.

b) A φ−3 induction motor has starting torque of 100% and a maximum torque of 200%

of the full load torque. Find the slip at maximum torque.

UNIT - IV

Q8) a) Explain in detail the principle of operation of an alternator.

b) Discuss the Synchronous Impedance method of computing the voltage regulation ofan alternator.

OR

Q9) a) Briefly explain the principle of operation of a synchronous motor.

b) Discuss the effects of varying excitation given to a synchronous motor.

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(Paper - VI) : Signals & Systems



Q1) a) What is linear time invariant system?

b) What are the limitations of energy and power signals?

c) What is causal system?

d) What is the significance of Fourier series?

e) Define Impulse response.

f) What is the relationship between convolution and correlation?

g) Define power spectral density.

h) What are incoherent signals?

i) Define Ergodic and non-Ergodic process.

j) What is thermal noise?

k) What is the relationship between bandwidth and rise time?

l) What are the conditions for the distortion less system?

m) List out the applications of Fourier Transform.

n) Draw the spectrum for Fourier transform of sine wave.

o) Express mathematically Fourier transform of constant amplitude.

UNIT - 1

Q2) a) Derive an Expression for signal approximation using orthogonal functions.

b) Obtain the relationship between the coefficient of Exponential Fourier series andTrigonometric Fourier series?

OR

Q3) a) Explain closed or complete set of orthogonal functions.

b) Determine the Fourier transform of the following functions:

i) x ( ) ( )[ ]32-3te)( −−+= tutut

ii) x ( ) {cos 1/2 t 1/2

0 otherwise

tt

π − ≤ ≤=

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UNIT - 2

Q4) a) A Filter has an input x( ) )(tuet t−= and the impulse response ( ) )(3 tueth t−= . Find

the Energy Spectral Density.

b) Explain Filter characteristics of linear system.

OR

Q5) a) Verify Parseval’s theorem for the Energy signal x( ) )(4 tuet t−= ?

b) Explain Causality and Paley - wiener criterion for physical Realization.

UNIT - 3

Q6) a) Explain Noise Figure, Noise Temperature & Noise Bandwidth with suitable examples?

b) A Receiver connected to an Antenna whose Resistance is 50Ω has an equivalent

noise resistance of 30Ω . Calculate the receiver’s noise figure in Decibels and itsequivalent noise temperature?

OR

Q7) a) A parallel tuned circuit is resonated at 200 MHz with a Q of 10, and a capacitance of10PF. The temperature of the circuit is 70ºC. What noise voltage will be observedacross the circuit by a wideband voltmeter?

b) Explain the concept of Power spectral density of White Noise?

UNIT - 4

Q8) a) Explain and Prove central limit theorem.

b) Consider the process x ( ) 10sin(200 )t t= +φ where φ is uniformly distributed the

interval ( ),− check whether the process is stationary or not?

OR

Q9) a) A box contains 2 Red, 3 Blue and 4 Black balls. 3 Balls are Drawn from the box atrandom. What is the probability that

i) The 3 balls are of different colors.

ii) Two balls are of the same colors and the third of different colors.

iii) All the balls are of the same color?

b) Derive the Wiener-Khinchin relationship.

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Documents

B.Tech. DEGREE EXAMINATION, MAY - 2013 … · · 2014-02-03... Write the form of Fourier series for f (x) in the interval 0 < x < 2π. e) ... 4 3, if 2 1 < x < 1, as the Fourier