Biju Patnaik University of Technology 2008-4th Sem B.Tech (B Tech) , network theory . - Question Paper

BPUT(B Tech) , fourth semester network theory ques. paper.

CPES 5201

Fourth Semester Examination - 2008 NETWORK THEORY Full Marks-70

Time: 3 Hours

Answer Question No. 1 which is compulsory I and any five from the rest.

The figures in the right-hand margin indicate marks.

1. Answer the following questions : 2x10

(i)    Give at least three properties of parallel resonance circuit.

(ii)    What are half power frequency points ? Explain.

(iii) What is the difference between an ideal filter and a practical filter ?

(iv)    Give the properties of a filter.

(v)    What are even and odd functions ? Give examples.

(vi)    What is the nature of the impulse response "i J of an RL circuit ?

united wc stand...

(vii)    For the band pass filter what is the normal characteristic impedance ?

(viii)    What is the value of ramp function at t=0 ?

(ix)    What is the reciprocal of a driving point function ?

(x)    State final value theorem.

2. (a) Define the following network functions with reference to a 2-port network : 4

(i)    driving point impedance

(ii)    transfer impedance.

(b) For the given network, find the transfer functions G₂₁(s), Z₂₁(s) and driving point impedance Z-s).    6

L

3. (a) What do you understand by :    4

(i)    zeros of a function, and

(ii)    zeros of transmission.

(b) What information do poles and zeros provide in respect of a network to which they relate ? Draw pole and zeros for: 6

s² +3s + 2 s² +7S + 12

And evaluate v(t) either analytically or by making use of pole-zero diagram.

4. (a) Derive the expression of Z-parameters in terms of other parameters.    5

(b) Calculate the Z-parameters, if the values of other parameters are given below : 5

(i)    A = 2, B = -1, C = 3 and D=-2

(ii)    h = 1, h₁₂ ⁼ 2, h₂₁ ⁼ 3, h₂₂ ⁼ 2

(iii)    Y₁₁=1/3, Y₁₂ = 2/3,Y₂₁ = -1/3, Y₂₂ =1/6 CPES 5201 4    Contd.

5. (a) Draw and discuss the profile of circuit parameters with frequency in a parallel resonant circuit.    3

(b)    Derive the relationship between Bandwitdth, Detuning Factor, Quality factor, Impedance and selectivity of a parallel resonant circuit.

3

(c)    A current source, having an internal resistance of 10 KQ feeds a tank circuit containing a coil (having L_c = 200 mH, R_C = 10Q) in parallel to a capacitor of 100 nF. Find the frequency of resonance and Q factor.    4

6. (a) Discuss the basic concept of working of low pass and high pass filters using reactive elements.    3 CPES 5201 5 P.T.O.

(b)    Analyze a prototype High Pass Filter. 3

(c)    Design the T and n section of a prototype High PassFilterhaving cut-off frequency of 20 kHz and design impedance of 450 Qs. Also find its characteristics impedance and phase constant at 25 kHz as well as determine the attenuation at4 kHz. 4

7. (a) Represents the given impedance function using Cauer-I form.    5

$ +n<J +4i

^(S)= s# + 2i

(b) Synthesize the Foster-ll form of given admittance function    5

(J +1|(J +5|

^Y(S)=3T

8. (a) Determine the effective value of f(t) of the waveform shown in the figure below. 5

(b) Obtain the Fourier coefficients for the function given by    5

f(t) = (t + 7t) when 7T<t< 7i; f(x+27t) =f(x)

Attachment: biju-patnaik-university-of-technology-2008-b-tech-36032-1.pdf

Earning:   Approval pending.