|''|'||||''|''||'|'| Code No: R21013 II B. Tech I Semester, Regular Examinations, Nov – 2012 ELECTRICAL AND ELECTRONICS ENGINEERING (Com. to CE, ME, CHEM, PE, AME, MM) Time: 3 hours Max. Marks: 75 All Questions carry Equal Marks Note: Answer any FIVE Questions, not exceeding Three Questions from any one part PART-A 1. a) State and explain Ohms law and its limitation b) Two resistances of Ω 50 and Ω 40 respectively are connected in parallel. A third resistance of Ω 10 is connected in series with the combination and a D.C supply of 220 V is applied to the ends of the completed circuit. Calculate the current in each resistance. 2. With a neat sketch explain the main parts of the DC machine and state the material of which each part is made and their function 3. a)From the fundamentals, derive the expression for the EMF equation of a single phase transformer. b) A transformer has a primary winding of 600 turns and a secondary turns of 300. When the load current on the secondary is 50A at 0.85 p.f lagging, the primary current is 25A at 0.707 lagging. Determine the no load current of the transformer and the phase angle with respect to the voltage. 4. a) Explain the slip-torque characteristics of three phase induction motor b) Find the no-load phase and line voltage of a star-connected 3-phase, 6-pole alternator which runs at 1200 rpm, having flux per pole of 0.1 wb sinusoidally distributed. Its stator has 54 slots having double layer winding. Each coil has 8 turns and the coil is chorded by 1 slot. PART-B 5. a) Explain the working of P-N junction diode b) What is a rectifier? Discuss the operation of half wave rectifier with a neat circuit diagram. 6. a) Explain the concept of feedback amplifier b) If a transistor with α = 0.96 and emitter to base resistance 80Ω is placed in common emitter configuration, find the gains of A i , A v , and A P ? 7. a) What are the various types of induction heating? b) Explain Dielectric Heating with a neat diagram. 8. Explain the following with neat diagram i) LVDT ii) Thermistors 1 of 1 R10 SET - 1
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Code No: R21013
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL AND ELECTRONICS ENGINEERING (Com. to CE, ME, CHEM, PE, AME, MM)
Time: 3 hours Max. Marks: 75
All Questions carry Equal Marks
Note: Answer any FIVE Questions, not exceeding Three Questions from any one part
PART-A
1. a) State and explain Ohms law and its limitation
b) Two resistances of Ω50 and Ω40 respectively are connected in parallel. A third resistance
of Ω10 is connected in series with the combination and a D.C supply of 220 V is applied to the
ends of the completed circuit. Calculate the current in each resistance.
2. With a neat sketch explain the main parts of the DC machine and state the material of which
each part is made and their function
3. a)From the fundamentals, derive the expression for the EMF equation of a single phase
transformer.
b) A transformer has a primary winding of 600 turns and a secondary turns of 300. When the
load current on the secondary is 50A at 0.85 p.f lagging, the primary current is 25A at 0.707
lagging. Determine the no load current of the transformer and the phase angle with respect to
the voltage.
4. a) Explain the slip-torque characteristics of three phase induction motor
b) Find the no-load phase and line voltage of a star-connected 3-phase, 6-pole alternator which
runs at 1200 rpm, having flux per pole of 0.1 wb sinusoidally distributed. Its stator has 54 slots
having double layer winding. Each coil has 8 turns and the coil is chorded by 1 slot.
PART-B
5. a) Explain the working of P-N junction diode
b) What is a rectifier? Discuss the operation of half wave rectifier with a neat circuit diagram.
6. a) Explain the concept of feedback amplifier
b) If a transistor with α = 0.96 and emitter to base resistance 80Ω is placed in common emitter
configuration, find the gains of Ai, Av, and AP?
7. a) What are the various types of induction heating?
b) Explain Dielectric Heating with a neat diagram.
8. Explain the following with neat diagram
i) LVDT ii) Thermistors
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Code No: R21013
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL AND ELECTRONICS ENGINEERING (Com. to CE, ME, CHEM, PE, AME, MM)
Time: 3 hours Max. Marks: 75
All Questions carry Equal Marks
Note: Answer any FIVE Questions, not exceeding Three Questions from any one part
PART-A
1. a) state and explain Kirchoffs laws
b) In the circuit shown in below figure, find the current in the each resistance.
2. Compare DC generator and DC motor with respect to principle of operation of mention the
application of each machine
3. a) Explain the principle of operation of transformer
b) In a 25 kVA, 2000/200V, 50Hz single phase transformer, the iron and full load copper losses
are 350 and 400 W respectively. Calculate the efficiency at unity power factor on full load and
half load.
4. a) Explain the principle of operation of alternator
b) A 3-phase induction motor has 2 poles and is connected to 400V, 50Hz, supply. Calculate
the actual rotor speed and rotor frequency when the slip is 4%.
PART-B
5. a)Draw and explain the equivalent circuit of the P-N junction diode
b) An a.c. voltage of peak value 20V is connected in series with a silicon diode and load
resistance of 500Ω. If the forward resistance of diode is 10Ω, find the following:
i) peak current through diode ii) peak output voltage
What will be these values if the diode is assumed to be ideal?
6. a)Explain the V-I characteristics of common emitter configuration
b) Explain the static characteristics of the SCR?
7. Explain the dielectric heating with necessary diagrams? List out its merits and give some
applications.
8. Explain the working principle of the following with neat diagrams
a) Strain gauge b) Piezo-electric transistors
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Code No: R21013
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL AND ELECTRONICS ENGINEERING (Com. to CE, ME, CHEM, PE, AME, MM)
Time: 3 hours Max. Marks: 75
All Questions carry Equal Marks
Note: Answer any FIVE Questions, not exceeding Three Questions from any one part
PART-A
1. A Wheatstone bridge consists of AB = 4Ω, BC=3Ω, CD=6Ω and DA=5Ω. A 10V cell is
connected between B and D and a galvanometer of 8Ω is connected between A and C. Find the
current through the galvanometer.
2. a) Derive the emf equation of a DC generator
b) A 4-pole DC motor is fed at 400V and takes an armature current of 35A. The resistance of
the armature circuit is 0.2Ω. The armature winding is wave connected with 800 conductors and
useful flux per pole is 0.023 Wb. Calculate the speed of the motor.
3. a) What are the different losses occurring in a transformer on load? and what are the tests
required for finding these losses.
b) Short-circuit test is conducted on a 5kVA, 400V/100 V single phase transformer with 100
V winding shorted. The input voltage at full load current is 40 V. The wattmeter, on the
input reads 250 W. Find the power factor for which regulation at full load is zero.
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Code No: R21013
4. a) Explain the regulation of alternator by synchronous impedance method
b) A 3-phase induction motor is wound for 4 poles and is supplied from 50 Hz systems.
Calculate (i) the synchronous speed, (ii) the speed of the motor when slip is 4% and (iii) the
rotor current frequency when the motor runs at 600 r.p.m.
PART-B
5. a) Explain the forward current, peak inverse voltage and reverse current in a P-N junction
diode
b) Compare half wave and full wave rectifiers and their output voltage waveforms
6. a) Explain the V-I characteristics of SCR?
b) A transistor is operated at a forward current of 2µA and with the collector open circuited .
Calculate the junction voltages Vc and Ve the collector to emitter voltage Vce assuming,
IC0=2µA , IE0=1.6µA, αn=0.98.
7. a) What are the various core type induction furnaces? Explain one of them.
b) Discuss the industrial applications of dielectric heating.
8. a) Explain the working of CRO with neat diagram.
b) Explain the working of digital multimeter.
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Code No: R21013
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL AND ELECTRONICS ENGINEERING (Com. to CE, ME, CHEM, PE, AME, MM)
Time: 3 hours Max. Marks: 75
All Questions carry Equal Marks
Note: Answer any FIVE Questions, not exceeding Three Questions from any one part
PART-A
1. a) Three equal resistances of value R ohms are connected in a delta fashion. This is to be
replaced by an equivalent star connected resistance R1, R2 and R3. What are the values of R1,
R2 and R3 in terms of R.
b) By applying Kirchhoff’s law, find the current through all the elements in the circuit as
shown in the figure?
2. a) What is DC generator and explain the basic principle of operation of a DC generator?
b) Derive the torque equation of a DC motor.
3. a) State and prove the condition for maximum efficiency of a transformer?
b) In a 25KVA, 2000/200V transformer the constant and variable losses are 350 W and 400 W
respectively calculate the efficiency on u.p.f at i) Full load and ii) Half full load.
4. a) Explain the principle of operation of alternator
b) A 6-pole, 3-phase, 50 Hz induction motor is running at full-load with a slip of 4%. The rotor
is star-connected and its resistance and standstill reactance are 0.25 Ω and 1.5 Ω per phase.
The e.m.f. between slip rings is 100 V. Find the rotor current per phase and p.f., assuming
the slip rings are short-circuited.
PART-B
5. a) With a neat circuit diagram, explain the operation of centre tap full wave rectifier
b) The applied input a.c. power to a half-wave rectifier is 100 watts. The d.c. output power
obtained is 40 watts. i) What is the rectifier efficiency? ii) What happens to remaining 60
watts?
6. a) Compare the characteristics of transistor amplifiers in the three configurations?
b) Explain the necessary conditions for oscillators
7. a) Explain the generation of ultrasonic’s and mention the applications
b) Explain the principle of induction heating.
8. a) Draw the schematic diagram of a CRO and explain its principle of working
b) Explain the working of a thermocouples.
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Code No: R21023
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL CIRCUIT ANALYSIS - I (Electrical and Electronics Engineering)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1. a) Explain the difference between independent and dependent source with suitable examples.
b) The voltage waveform shown in figure 1 is applied to a pure capacitor of 60 µF. Sketch i(t)
and p(t) and determine Imax and Pmax .
2. a) For the circuit shown in figure 2, use nodal analysis to determine voltage across 3 Ω and 12 Ω
resistance. Compute power absorbed by 6 Ω resistor.
b) Calculate the mesh currents in the network shown in Figure 3.
3. a) Construct the phasor and impedance diagram and determine the circuit constants for the
following voltage and current.
) sin(5000ttV050150)( += V, )- sin(5000tti
0255)( =
b) A current of 4 A flows through a non-inductive resistance in series, with a choking coil when
supplied at 230 V, 50 Hz. If the voltage across the resistance is 100 V and across the coil is 180
V, draw the phasor diagram and calculate i) impedance, reactance and resistance of the coil
ii) the power absorbed by the coil iii) the total power.
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Code No: R21023
4. a) A series RLC circuit with R = 100 Ω, L = 0.5 H and C =40 µF has applied voltage of 100V
with variable frequency. Calculate the resonant frequency, current at resonance, voltage across
R, L and C. Also calculate the Q-factor, upper and lower half power frequencies and
bandwidth.
b) Construct an admittance locus and determine the variable inductance values, so that the phase
angle between the supply voltage and supply current is zero for the circuit shown in Fig. 5.
Assume ω = 5000 rad/sec.
5. a) Two coils with inductances in the ratio of 5:1 have a coupling coefficient k = 0.5. When these
coils are connected in series aiding, the equivalent inductance is 44.4 mH. Find L1, L2 and M.
b) In the network shown in figure 6, determine the value of the load impedance (ZL) for
maximum power transfer.
6. a) Draw the graph of the network given in figure 7, find tie test schedule and determine loop
currents.
b) Draw a graph of the network shown in figure 8. Select a tree with branches R1, R2, R5, R3 and
R4.Write fundamental loop matrix and cut set matrix.
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2Ω
2Ω
2Ω
2Ω 4 A 10 V
+
-
2Ω
Figure 7
R1
R3
R5
R2 R4 R6
R7
R8
R9
Figure 8
5 Ω
20 µF
7 Ω ~ 100 V
Fig. 5
XL
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Code No: R21023
7. a) Find the current in 10 Ω resistance of the circuit shown in figure 9 using Millman’s theorem.
b) In the network given in figure 10, impedance Ω∠=0
1 020Z be connected between the
terminals A and B. Find the power dissipated in the above impedance.
8. a) Find VL in the circuit shown in figure 11, using superposition theorem.
b) Verify the Tellegen’s theorem for the circuit shown in Figure 12.
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5Ω
10 Ω
j10 Ω
j5 Ω
5 Ω
A
B
50 00
V
Figure 10
5 A 2V
+
-
RL VL
1Ω
1Ω +
-
2Ω
5 A
Figure 11
50 V
+
-
2Ω 3Ω
5Ω
5Ω 2Ω
Figure 12
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Code No: R21023
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL CIRCUIT ANALYSIS - I
(Electrical and Electronics Engineering)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1. a) Explain the principle of source transformation using suitable examples.
b) A pure inductance of 3 mH carries a current of the waveform shown in figure 1. Sketch the
waveform of v(t) and p(t). Determine the average value of power.
2. a) Using nodal analysis, find current i in the circuit shown in figure 2.
b) Find the source currents in the resistance network shown in figure 3 by using Y- ∆ transformation.
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R10 SET - 2
1 3 5 7 8 4
t (milli-sec)
10A
-10 A
i(t)
Figure 1
1 KΩ 2 mA
12 mA
3 KΩ 6 mA
2 KΩi
Figure 2
d
2 Ω
5 Ω
3 Ω
a
b
c
5 V
8 Ω
5 Ω
Figure 3
+
-
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Code No: R21023
3. a) In an electrical circuit R, L and C are connected in parallel. R = 10 Ω, L= 0.1 H and C = 100
µF. The circuit is energized with supply at 230 V, 50 Hz. Calculate (i) the impedance ii)
current taken from the supply (iii) power factor of the circuit and power consumed by the
circuit.
b) Find the currents flowing through different elements in the circuit shown in figure 4.
4. a) In a series resonance circuit, the resistance is 5 Ω, the resonant frequency is 4×105 rad/sec and
the bandwidth is 104 rad/sec. Compute L and C of the network, half-power frequencies and Q
of the circuit.
b) Draw the admittance locus for the circuit shown in figure 5 and calculate C which results in
resonance when ω= 5000 rad/sec.
5. a) Discuss about the analogy between magnetic and electric circuits.
b) For the circuit shown in figure 6, find the voltage across j5 Ω reactance.
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Code No: R21023
6. a) Define the following.
i) Tree ii) co-tree iii) cut-set iv) Loop
b) Draw the graph of the network shown in figure 7. Find the tie set schedule, obtain
equilibrium equation on loop current basis and find the branch currents.
7. a) Find Norton’s equivalent circuit for the circuit shown in Figure 8.
b) Find the current through 15 Ω resistance using Millman’s theorem for the circuit shown in
Figure 9.
8. a) Find ‘i' using super position theorem for the circuit given in figure 10.
b) Verify the reciprocity theorem for the circuits given in figure 11.
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R10 SET - 2
+
5Ω
10 V -
5Ω
5Ω
5Ω
5Ω
5Ω
1
2 3 Figure 7
2 A 6 V
+
-
1Ω Vx
5Ω +
-
+ -
5Vx
i
Figure 10
5 Ω
~
1 Ω 4 Ω
j2 Ω -j4 Ω
V 0
9010∠5 Ω
~
1 Ω 4 Ω
j2 Ω -j4 Ω
V 09010∠
Figure 11
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Code No: R21023
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL CIRCUIT ANALYSIS - I (Electrical and Electronics Engineering)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1. a) Define Ohm’s law. Explain about ideal and non-ideal voltage and current sources.
b) The waveform given in figure 1 is the voltage across a linear time invariant inductor of 2H.
If iL(0) = 0, sketch the waveform of current i(t) up to 3 sec.
2. a) Write a set of node-voltage equations for the network shown in Figure 2 and solve all node
voltages.
b) Find the current in 3 Ω resistor and voltage across the current source in the network shown in
Figure 3 using mesh analysis.
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0 1 2 3
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Code No: R21023
3. a) When a resistor and choke coil in series are connected to a supply of 240 V, a current of 3 A
flows lagging the supply voltage by 400. The voltage across the inductor is 180 V. Find the
resistance of the resistor and the parameters of the coil.
b) Determine the branch currents and the current supplied by the mains in the circuit shown in
Figure 4.
4. a) Show that in a series RLC circuit, 21 fff0 = , where fo is the resonant frequency and f1, f2
are half power frequencies.
b) For the circuit shown in figure 5, draw the admittance locus and sate whether resonance is
possible.
5. a) Explain the concept of mutual inductance and derive the expression for coefficient of
coupling.
b) Determine the voltage V across the 10 Ω resistor in the magnetically coupled circuit shown
in Figure 6.
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R10 SET - 3
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Code No: R21023
6. a) Calculate the source current for the circuit shown in figure 7 using network topology.
b) Draw the dual of the network shown figure 8.
7. a) Find the value of ZL to be connected between the terminals AB of the circuit shown in figure
9, for maximum power transfer. Find maximum power.
b) Find the voltage V using Norton’s theorem for the circuit shown in Figure 10.
8. a) Show the validity of reciprocity theorem for the circuits shown in figure 11.
b) Find V0 in the network shown in figure 12 using superposition theorem.
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10 Ω
5Ω
50 V
10Ω
+
-
10Ω 20Ω
10 Ω
5Ω
50 V
10Ω
+ 10Ω
20Ω
-
2Ω
1Ω
4 V 2Ω
+
- 1Ω
1Ω
Figure 7
Figure 8
S1
4 A
C2=4 F
L1=3H
R1=1 Ω
2V
+
-
R2=2 Ω
L2=2H
R3=3 Ω
S2
Figure 11
1 A 10V
+
- 2Ω
0.5V0 V0
5Ω
+
-
+ - 1Ω 4V
+
-
Figure 12
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Code No: R21023
II B. Tech I Semester, Regular Examinations, Nov – 2012
ELECTRICAL CIRCUIT ANALYSIS - I (Electrical and Electronics Engineering)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~~~~
1. a) The waveform shown in the below Figure 1 has a period of 10secs
i) What is the average value of the current over one period?
ii) How much charge is transferred in the interval 1 < t < 14 secs?
iii) If q(0)=0, sketch q(t), 0 < t < 16secs.
b) A current of the waveform shown in figure 2, flows through a capacitor C = 25 µF. Sketch
the voltage waveform and determine Vmax and qmax.
2. a) Use nodal analysis to find currents in different resistances of the circuit given in Figure 3.
b) Find the currents I1, I2, and I3 in the circuit given in Figure 4, using node voltage analysis
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-4
Time in sec
i(A)
2 4 6 8
10
12 14 16 18 -2
4
2
8
6
Figure 1
5A
-5A
i(t)
Time in macro secs
Figure 2
2
3
4 5 0
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Code No: R21023
3. a) A series combination of R and C is in parallel with a 25 Ω resistor. A 50 Hz source results in
a total current of 6.5 A, a current of 5 A through 25 Ω resistance and a current of 2.3 A in the
RC branch. (i) Draw the phasor diagram of the circuit and find values of R and C (ii) Find
apparent, active, reactive power and power factor of the circuit.
b) A resistance and inductance are connected in series across a voltage given by
t tv ω= sin283)( . The power drawn by the series combination is 400 W and the current has a
maximum value of 4 A. Determine the circuit parameters and the power factor of the circuit.
4. a) In a series RLC network, R = 50 Ω and C = 20 µF, and L = 50 mH. Find the voltage across
each element, when the voltage across the resistor is a maximum, given that the applied voltage
is 100 V with a variable frequency.
b) Using the locus diagrams, determine the value of RL for which the circuit shown in figure 5
will be under resonance.
5. a) Two coupled coils with L1 = 0.01 H and L2 = 0.04 H and k = 0.6 can be connected in four
different ways such as series aiding, series opposing, parallel aiding and parallel opposing. Find
equivalent inductance in each case.
b) For the circuit shown in figure 6, determine the currents i1 & i2 using loop method of analysis.
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R10 SET - 4
10 Ω
-j 5Ω
j 10 Ω
~ RL
100 V
Fig. 5
j 2Ω
V2=10 00 V i2
i1
j4 j3 V1=10 0
0V
-j8Ω 2Ω
Figure 6
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Code No: R21023
6. a) For the network given in figure 6A, draw its dual and write KCL in matrix form of the dual
network.
b) For the network given in figure 6B, calculate the branch voltages and branch currents using
node- basis method.
7. a) Use the Thevinin’s theorem to find the deflection of galvanometer having a resistance of
100 ohm and a sensitivity of 0.5x10-5
A per mm connected to terminals AB of the bridge shown
in Figure 7.
b) Find the voltage across 10 Ω resistance in the network shown in Figure 8 using Norton’s
theorem.
8. a) Use superposition to determine voltage Vx in the network given in Figure 9.
b) Verify Tellegen’s theorem for the below circuit shown in Figure 10.
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40
10Ω
50Ω
20Ω
88V
+
-
10
Figure 10
L
R1 S
V
+
-
R2
C
Figure 6A
1Ω
1 V +
-
1Ω
2Ω
1Ω 1Ω 2Ω
Figure 6B
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Code No: R21042
II B. Tech I Semester, Regular Examinations, Nov – 2012
NETWORK ANALYSIS (Com. to ECE, EIE, ECC)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1. a) What are the types of sources? Explain them with suitable diagrams and characteristics?
b) Calculate the voltage that is to be connected across terminals x-y is shown in below figure
such that the voltage across the 2Ω resister is 10 V. Also find Ia and Ib .what is the total
power loss in the circuit.
2. Explain the principles of duality? Write a graphical procedure to draw a dual network?
A periodic voltage waveform has been shown in the below figure. Determine the following.
i) Frequency of the waveform ii) Wave equation for 0< t <100 m sec
iii) R.M.S. value and iv) Average value
3. a) Define the following
i) Impedance ii) Phase angle iii) Power factor
b) State and explain star-delta conversion in AC systems.
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SET - 1 R10
x Ib
2 Ω
y
5 Ω
Ia
6 Ω
4 Ω
V(t)
Vm
t (ms) π 2π 0
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Code No: R21042
4. For the network shown in below figure, find the voltage across load resistance RL.
5. Find the current through the capacitor of –j5Ω reactance as shown in below figure using
superposition theorem
6. Find the open circuit impedance parameters of the circuit shown in below figure. Also find the
Y-parameters
7. In the network shown in below figure, the switch is closed at t= 0. Find the value of current in
each loop.
8. a) What are the properties of filters
b) Design an m-derived T-section low pass filter having cut off frequency, fc=7000Hz, design
impedance Ro=600Ω and frequency of infinite attenuation.
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SET - 1 R10
RL=5Ω 50 V
k=0.5
~
j2Ω j5Ω
-j3Ω
2Ω V1 2V1
1Ω I1
3Ω
4Ω I2
V2
10Ω
t=0
5Ω
100 V
1H 3H
20Ω
2Ω 00100 ∠V
j4 Ω
-j5Ω 3Ω
~ 5Ω A I03010∠=
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Code No: R21042
II B. Tech I Semester, Regular Examinations, Nov – 2012
NETWORK ANALYSIS (Com. to ECE, EIE, ECC)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1. a) What are the network elements? Explain them
b) What is the magnitude of current drained from the 10V source in the circuit shown below?
2. a) Define the following terms
i) Node ii) Tree iii) Incidence matrix iv) Basic tie set
b) A non-alternating periodic waveform has been shown in below figure. Find its form factor
and peak factor
3. a) Obtain the expressions for star-delta equivalence of impedance network.
b) A two element series circuit is connected across AC source V )t sin(te0
202200)( +ω= .
The current in the circuit then found to be A. )tcos( ti025210)( −ω= Determine the parameters
of the circuit.
4. a) Derive the expression for bandwidth of series RLC circuit.
b) Two coils with 300 turns and 700 turns are wound side by side on a closed magnetic circuit
of area of cross section 400cm2 and mean length 80 cm, the magnetic circuit has relative
permeability of 4000. Determine the mutual inductance, self induced e.m.f and mutually
induced e.m.f when the current in the coil with 300 turns grows from zero to 25A in a time
of 0.3 sec
1 of 2
SET - 2 R10
3Ω
P
10V
5Ω
2Ω
Q
1Ω
2Ω 3Ω
x(t)
2A
t (ms) 10 20 0
1A
30 40
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Code No: R21042
5. Obtain equivalent circuit across A-B terminals in figure shown below and find the value of ZL
to have maximum power.
6. Determine Y-parameters of the network shown in below figure
7. Using Laplace transformation technique, find current in each loop at t = 0+ following switching
at t = 0 of switch K is shown in below figure. Assume the network previously de-energized.
8. a) What are the classifications of filters? Discuss them briefly.
b) Design a constant k-low pass filter having fc = 2 kHz and design impedance Ro=600Ω.
Obtain the value of attenuation at 4 kHz.
2 of 2
SET - 2 R10
2Ω
100 V
Aj3Ω
ZL ~ j2Ω j4Ω
j1Ω
B
2Ω V1
3Ω I1
4Ω
I2
V2 3I2
2Ω
K
3Ω
10 V
1H 1H
4Ω
+
-
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Code No: R21042
II B. Tech I Semester, Regular Examinations, Nov – 2012
NETWORK ANALYSIS (Com. to ECE, EIE, ECC)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1. a) Explain the source transformation techniques with suitable circuits.
b) Find mesh currents and determine voltage across each element in the circuit shown in below
Figure.
2. a) Explain the RMS value and average value of alternating quantity. Derive its necessary
expressions.
b) Find the branch currents shown in below figure by using the concept of the tie-set matrix.
3. In the two-mesh network shown in below figure, determine the
a) Mesh currents
b) Power supplied by the source and
c) Power dissipated in each resistor
1 of 2
SET - 3 R10
8Ω
10 V
-
2Ω
5Ω
5A
+
4Ω
5Ω
6Ω
3Ω
25V
1Ω
2Ω
2Ω
+
-
j4Ω
2Ω
100 V 1Ω ~
-j5Ω -j3Ω 3Ω
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Code No: R21042
4. a) Determine the coefficient of coupling of two magnetically coupled coils of turns N1 and N2
b) For the circuit shown in below figure, find the value of Xc in ohms at which the circuit under
resonance
5. In the circuit shown in below figure, find the current through RL connected across A-B
terminals by utilizing Thevenin’s theorem. Verify the results by Norton’s theorem.
6. For the network shown in below figure, find ABCD parameters
7. In the network shown in below figure find the current through the inductor for all values of‘t’.
8. a) Explain the concept of m-derived filters.
b) Design a prototype band stop filter section having cut-off frequencies of 2000 Hz and 5000
Hz and design resistance of 600Ω.
2 of 2
SET - 3 R10
5Ω
j3 Ω -jXC
8Ω
2Ω
j5 Ω
4Ω 5 A ~ 25 V
5Ω A
B
1Ω
2Ω
3Ω
5Ω 1
11
2
21
S1
2Ω 10 V 3Ω
+
-
4Ω
S2
1 H
t=0 t=1
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Code No: R21042
II B. Tech I Semester, Regular Examinations, Nov – 2012
NETWORK ANALYSIS (Com. to ECE, EIE, ECC)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1. a) State and explain Kirchhoff’s laws.
b) Using nodal analysis techniques to determine current ‘i’ in the network shown in below
figure.
2. a) Define the following
i) Time period ii) Frequency iii) RMS value iv) Average value
b) Draw the dual of the network shown in below figure and explain its procedure.
3. Find the source voltage ‘Vs’ by using nodal technique, assume I = 5 /450 A.
4. a) Contrast between magnetic circuits and electrical circuits.
b) A series RLC circuit has the following parameters. R = 15 ohms, L = 2H, C = 100 micro F.
Calculate the resonant frequency. Under resonant condition, calculate current, power, and
voltage drops across various elements, if the applied voltage is 100V.
1 of 2
SET - 4 R10
5A
6Ω
i
4Ω
3i
10Ω 3A
S V
I
C2
L G1
+
-
G2
C1
VS
I
~
2Ω
-j4Ω
3Ω j4Ω
3Ω
-j2 Ω
j5Ω
4Ω
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Code No: R21042
5. Find the current through the 10 ohm resistor in the following circuit using Norton’s Theorem.
6. Obtain Z-parameters and transmission parameters of the network shown in below figure.
7. In the below figure, the initial voltage in the capacitor is 1V as the polarity shown. Find the
voltage appearing across the capacitor with application of the step voltage
8. a) Explain the analysis of band pass filter.
b) Design a T-section constant K-high pass filter having cut-off frequency of 10 kHz and design
impedance R0 = 600 ohms. Find its characteristic impedance and phase constant at 25 kHz.
2 of 2
SET - 4 R10
10V 1Ω
~
-j2Ω 5Ω
+ ~
+ V
0305∠
2Ω
10Ω
A
B
5Ω
V1
2Ω I1
4Ω
I2
V2 3I1
+
2 u(t)
4Ω I1
-
3I1
2Ω
1 F +
-
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Code No: R21052
II B. Tech I Semester, Regular Examinations, Nov – 2012
PROBABILITY AND STATISTICS (Com. to CSE, IT)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1. a) Four cards are drawn from a pack of cards. Find the probability that i) all are diamonds
ii) there is one card of each suit, and (iii) there are two spades and two hearts.
b) A bag X contains 2 white and 3 red balls and a bag Y contains 4 white and 5 red balls.
One ball is drawn at random from one of the bags and is found to be red. Find the probability
that it was drawn from bag Y.
2. a) A random variable X has the following probability function :
Values of X,
x 0 1 2 3 4 5 6 7
P(x) 0 k 2 k 2 k 3 k 2k
2 2k
7 2k + k
i) Find k , ii) Evaluate ( 6), ( 6), (3 6)p X p X p X< ≥ < ≤
iii) Find the minimum value of x so that 1
( ) .2
p X x≤ >
b) Let X be a continuous random variable with distribution :
1, 0 3
( ) 6
0
x k if xf x
elsewhere
+ ≤ ≤
=
i) Evaluate k ii) Find ( ).21 ≤≤ XP
3. a) Assume that on the average one telephone number out of fifteen called between 2 P.M.
and 3 P.M. on week-days is busy. What is the probability that if 6 randomly selected
telephone numbers are called i) not more than three ii) at least three of them will be busy?
b) In a normal distribution, 31% of the items are under 45 and 8% are over 64. Find the mean
and standard deviation of the distribution?
4. a) A population consists of the four numbers 1, 5, 6, 8. Consider all possible samples of size
two that can be drawn without replacement from this population. Find i) The population
mean, ii) The population standard deviation, iii) The mean of the sampling distribution of
means, iv) The standard deviation of the sampling distribution of means.
b) Determine a 95% confidence interval for the mean of a normal distribution with variance
2σ = 9 , using a sample of 100n = values with mean 5.x =
1 of 2
SET - 1 R10
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Code No: R21052
5. a) In a random sample of 100 tube lights produced by company A, the mean life time of tube
light is 1190 hours with standard deviation of 90 hours. Also in a random sample of 75 tube
lights from company B the mean life time is 1230 hours with standard deviation of 120
hours. Is there a difference between the mean lifetimes of the two brands of tube lights at a
significance level of 0.01?
b) An urban community would like to show that the incidence of breast cancer is higher than
in a nearby rural area. If it is found that 20 of 200 adult women in the urban community have
breast cancer and 10 of 150 adult women in the rural community have breast cancer, can we
conclude at the 0.05 level of significance that breast cancer is more prevalent in the urban
community?
6. a) The mean life of 10 electric motors was found to be 1450 hrs with a S.D. of 423 hrs. A
second sample of 17 motors chosen from a different batch showed a mean life of 1280 hrs
with a S.D. of 398 hrs. Is there a significant difference between the means of the two
samples? Use a 0.01 level of significance.
b) In two independent samples of sizes 8 and 10 the sum of squares of deviations of the
sample values from the respective sample means were 84.4 and 102.6. Test whether the
difference of variances of the populations is significant or not. Use a 0.05 level of
significance.
7. a) The following data show the values of sample mean X and the range R for the sample of size
5 each. Calculate the values for central line and control limits for mean-chart and range chart
and determine whether the process is in control
2 3 4( 5, 0.577, 0, 2.115 )Given n A D D= = = =
8. a) Explain briefly the main characteristics of Queuing system?
b) The arrival rate of customers at a counter in a bank follows Poisson distribution with a
mean of 45/hour; service rate of the clerk follows Poisson distribution with a mean of
60/hour. Find the probability of having 0, 5, 10 customers in the system. Find sL , qL , sW and
qW .
2 of 2
Sample No. 1 2 3 4 5 6 7 8 9 10
Mean( X ) 43 49 37 44 45 47 51 46 43 47
Range(R) 05 06 05 07 07 04 08 06 04 06
SET - 1 R10
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Code No: R21052
II B. Tech I Semester, Regular Examinations, Nov – 2012
PROBABILITY AND STATISTICS (Com. to CSE, IT)
Time: 3 hours Max. Marks: 75
Answer any FIVE Questions
All Questions carry Equal Marks
~~~~~~~~~~~~~~~~~~~~~~
1. a) In a given race, the odds in favor of four horses A, B, C, D are 1:3, 1:4, 1:5, 1:6 respectively.
Assuming that a dead heat is impossible; find the chance that one of them wins the race.
b) In a bolt factory, machines A, B and C manufacture respectively 25%, 35% and 40% of the
total. Of their output 5, 4 and 2 percent are defective bolts. A bolt is drawn at random from the
product and is found to be defective. What is the probability that it was manufactured by
machine B?
2. a) A random variable X has the following probability function :
Values of X,
x 0 1 2 3 4 5 6 7 8
P(x) a 3a 5a 7a 9a 11a 13a 15a 17a
i) Determine the value of a,
ii) Evaluate ( ) ( ) ( )52,3,3 <≤≥< XPXPXP .
b) Let X be a continuous random variable with distribution :
10 8
( ) 8
0
if xf x
elsewhere
≤ ≤
=
Find i) ( )52 ≤≤ XP ii) ( )73 ≤≤ XP iii) ( )6≤XP iv) Determine and plot the graph
of the cumulative distribution function F of X.
3. a) Out of 800 families with 4 children each, how many families would be expected to have (i) 2
boys and 2 girls (ii) at least one boy (iii) no girl (iv) at most two girls? Assume equal
probabilities for boys and girls.
b) In a normal distribution, 7% of the items are under 35 and 89% are under 63. What are the
mean and standard deviation of the distribution?
4. a) A population consists of the four numbers 1, 5, 6, 8. Consider all possible samples of size two
that can be drawn with replacement from this population. Find i) The population mean,
ii) The population standard deviation, iii) The mean of the sampling distribution of means,
iv) The standard deviation of the sampling distribution of means
b) Determine a 99% confidence interval for the mean of a normal distribution with variance
2σ = 4 , using a sample of 200n = values with mean 10=x
1 of 2
SET - 2 R10
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Code No: R21052
5. a) A manufacturer claims that the average tensile strength of thread A exceed the average tensile
strength of thread B by at least 12 kilograms. To test his claim, 50 pieces of each type of thread
are tested under similar conditions. Type A thread had an average tensile strength of 86.7
kilograms with known standard deviation of 6.28Aσ = kilograms, while type B thread had an
average tensile strength of 77.8 kilograms with known standard deviation of 5.61Bσ =
kilograms. Test the manufacturers claim at 0.05 level of significance.
b) In a study to estimate the proportion of residents in a certain city and its suburbs who favor
the construction of a nuclear power plant, it is found that 63 of 100 urban residents favor the
construction while only 59 of 125 suburban residents are in favor. Is there a significant
difference between the proportion of urban and suburban residents who favor construction of the
nuclear plant? Use a 0.05 level of significance.
6. a) Two samples of sodium vapor bulbs were tested for length of life and the following results
were returned :
Size Sample mean Sample S.D.
Type I 8 1234 hrs 36 hrs
Type II 7 1036 hrs 40 hrs
Is the difference in the means significant to generalize that type I is superior to type II regarding
length of life? Use a 0.05 level of significance.
b) Two independent samples of size 9 and 8 had the following values of the variables:
Do the estimates of the population variance differ significantly? Use a 0.05 level of
significance.
7. The following data show the values of sample mean X and the range R for
The sample of size 5 each. Calculate the values for central line and control limits for mean-chart
and range chart and determine whether the process is in control
3. a) Draw the equivalent circuit of hybrid-π model and derive the expressions for Hybrid-π
impedances in terms of low frequency h-parameters.
b) The following low-frequency parameters are available for a transistor at
ICQ = 5 mA
hie = 1K, hfe = 100 hoe = 4 x 10-5
A/V
hre = 10-4
Cob = 2 pF fT = 10 MHz
Compute the values of hybrid-π parameters at room temperature. (8M+8M)
4. a) Show that class B push pull amplifiers exhibit half wave symmetry.
b) A power transistor is to be used as a class A transformer coupled amplifier and is to deliver a
maximum of 10W to a 4 ohm load. Operating point is adjusted for symmetrical clipping
with collector supply voltage of 15V. Assume ideal characteristics with Vmin = 0V.
Calculate.
Transformer turns ratio.
Peak collector current
Operating point values of ICQ and VCEQ.
Power dissipation rating of transistor.
Collector circuit efficiency. (8M+8M)
1 of 2
SET - 4 R07
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Code No: X0425
5. a) Derive the expression for the gain of a Single-tuned inductively coupled amplifier. Discuss
about its bandwidth.
b) A parallel resonant circuit comprises of an inductor (having inductance of 1mH and
resistance of 10Ω) and a parallel capacitor of 100 pF.
Calculate:
Resonant frequency, ignoring the resistance.
Resonant frequency, considering the resistance.
Q-factor.
Impedance at resonant frequency. (8M+8M)
6. a) What is stagger tuning? How it is different from synchronous tuning? Derive an expression
for the selectivity of a stagger tuned amplifier.
b) Write notes on wide band tuned amplifiers. (8M+8M)
7. a) Define the terms: i) Load Regulation ii) Line Regulation iii) Ripple Rejection and
iv) Temperature Stability pertaining to voltage regulator ICs.
b) A shunt regulator utilizes a Zener diode whose voltage is 5.1 V at 50 mA and whose rz = 7Ω.
The diode is fed from a 15V DC supply through a 200 Ω resistor. What is the output voltage
at no load? Find the line and load regulations. (8M+8M)
8. a) Draw the circuit for 7805 Voltage Regulator IC and explain its working.
b) Design a voltage regulator using IC 723 for 5 V output and 3A load current. Vin = 10V,
VSC = 0.65V. (8M+8M)
2 of 2
SET - 4 R07
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Code No: X0524/R07 Set No. 1
II B.Tech I Semester Supplementary Examinations, November 2012DIGITAL LOGIC DESIGN
( Common to Computer Science & Engineering, Information Technologyand Computer Science & Systems Engineering)
Time: 3 hours Max Marks: 80Answer any FIVE Questions
All Questions carry equal marks? ? ? ? ?
1. Convert the following to Decimal and then to Octal.
(a) 123416
(b) 12EF 16
(c) 101100112
(d) 100011112
(e) 35210
(f) 99910 [3+3+3+3+2+2]
2. (a) Write short notes about the various digital logic families.
(b) Obtain the complement of the following Boolean expressions.
i. AB + A(B + C) + B’(B + D)
ii. A + B + A’B’C.
(c) Obtain the dual of the following Boolean expressions.
i. A’B + A’BC’ + A’BCD + A’BC’D’E
ii. ABEF + ABE’F’ + A’B’EF. [8+4+4]
3. (a) Draw the multiple level NOR circuit for the following expression:A (B + C + D) + BCD
(b) Simplify the following functions and implement two level NOR gates: [8+8]
i. f (A,B,C,D) = Σ0, 2, 4, 6, 8, 9, 10, 11, 12
ii. F (w, x, y, z) = Σ5, 6, 9, 11
4. (a) If F1 (A,B,C,D) = Σ (1, 3, 4, 5, 9, 10, 11) + d (6, 8) andF2 (A,B,C,D) = Π (1, 3, 5, 6, 10, 11, 13, 14) + d (9, 12)
Design a minimal SOP logical circuit for F3 (A,B,C,D) = F1 ⊕ F2
Draw the circuit using NOR- gates.
(b) Design a Code converter circuit to convert 9’s complement code to BCD codeusing Full-adders and additional gates. (Use block diagram of Full adders).
[8+8]
5. A sequential circuit with 3 D-flip-flops A, B and C has only one input ‘X’ and oneoutput ‘X’ with following relationshipDA = B ⊕ C ⊕X, DB = A, DC = B
1 of 2
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Code No: X0524/R07 Set No. 1
(a) Draw the logic diagram of the circuit.
(b) Obtain logic diagram, state table and state diagram. [16]
6. (a) What is the maximum frequency required for a 10-bit ripple counter andsynchronous counter, if the propagation delay of the flip flop is 10ns.
(b) Design a clocked sequential circuit to detect 1111 or 0000. Overlapping isallowed. Draw the circuit using flip flops. [6+10]
7. (a) Give the HDL code for a memory read , write operations if the memory sizeis 64 words of 4 bits each. Also explain the code
(b) Obtain the 15-bit Hamming code for the 11-bit data word 11001001010. [8+8]
8. (a) Explain critical and non critical races with the help of examples.
(b) An asynchronous sequential circuit has two internal states and one output.The excitation and output functions describing the functions are: [6+10]
Y1 = x1x2 + x1y′2 + x′
2y1Y2 = x2 + x1y
′1y2 +x′
1y1Z = x2 + y1
i. Draw the logic diagram of the circuit.
ii. Derive the transition table and output map.
iii. Obtain a flow table for the circuit.
? ? ? ? ?
2 of 2
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Code No: X0524/R07 Set No. 2
II B.Tech I Semester Supplementary Examinations, November 2012DIGITAL LOGIC DESIGN
( Common to Computer Science & Engineering, Information Technologyand Computer Science & Systems Engineering)
Time: 3 hours Max Marks: 80Answer any FIVE Questions
All Questions carry equal marks? ? ? ? ?
1. (a) Explain different methods used to represent negative numbers in binary sys-tem. [6]
(b) Perform the subtraction with the following unsigned binary numbers by takingthe 2’s complement of the subtrahend. [5×2]
i. 11010 - 10010
ii. 11011-1101
iii. 100-110000
iv. 1010100-1010100
v. 11-1011.
2. (a) Reduce the following Boolean Expressions.
i. AB + A(B + C) + B’(B + D)
ii. A +B + A’B’C
iii. A’B + A’BC’ + A’BCD + A’BC’D’E
iv. ABEF + AB(EF)’ + (AB)’EF.
(b) Obtain the Dual of the following Boolean expressions.
i. x’yz’+ x’yz’ + xy’z’ + xy’z
ii. x’yz + xy’z’ + xyz + xyz’
iii. x’z + x’y + xy’z + yz
iv. x’y’z’ + x’yz’ + xy’z’ + xy’z + xyz’. [8+8]
3. (a) Construct K-map for the following expression and obtain minimal SOP ex-pression. Implement the function with 2-level NAND -NAND form.f (A,B,C,D) = (A + C + D)
(A + B + D
) (A + B + C
) (A + B + D
) (A + B + D
)(b) Implement the following Boolean function F using the two - level form:
i. NAND-AND
ii. AND-NOR F (A,B,C,D) = Σ0, 1, 2, 3, 4, 8, 9, 12 [8+8]
4. (a) Using five lower - order demultiplexer, construct 6 to 64 line demultiplexercircuit. Use only block diagrams.
(b) Design a Combinational logic circuit with three inputs A, B, C and threeoutputs x, y, z. If the binary input is 0, 1, 2, or 3, the binary output is onegreater than the input. When the binary input is 4, 5, 6, or 7, the binaryoutput is one less than the input. Draw the circuit using three-2 input ANDgates, one 3 input OR gate, one 3 input X - OR gate and one inverter. [4+12]
1 of 2
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Code No: X0524/R07 Set No. 2
5. (a) Draw the circuit diagram of clocked D- flip-flop with NAND gates and explainits operation using truth table. Give its timing diagram.
(b) Explain the procedure for the design of sequential circuits with example. [8+8]
6. A counter is to be designed to count either in 5421 code or 8421 code based on acontrol signal input. Draw the state diagram for such a counter and synthesize itusing T flip flops. Assume that the control signal cannot change in the middle of acounting sequence. [16]
7. (a) What is parity checking? Explain its necessity and how is it implemented?
(b) If the Hamming code sequence 1100110 is transmitted & due to error in oneposition, is received as 1110110, locate the position of the error bit using paritychecks and give the method for obtaining the correct sequence. [8+8]
8. (a) Describe the operation of the SR Latch using NAND gate with the help oftruth table, transition table and the circuit.
(b) An asynchronous sequential circuit has two internal states and one output.The excitation and output functions describing the functions are:Y1 = x1x2 + x1y
′2 + x′
2y1Y2 = x2 + x1y
′1y2 +x′
1y1z= x2 + y1 Implement the circuit defined above with NAND SR latches. [8+8]
? ? ? ? ?
2 of 2
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Code No: X0524/R07 Set No. 3
II B.Tech I Semester Supplementary Examinations, November 2012DIGITAL LOGIC DESIGN
( Common to Computer Science & Engineering, Information Technologyand Computer Science & Systems Engineering)
Time: 3 hours Max Marks: 80Answer any FIVE Questions
All Questions carry equal marks? ? ? ? ?
1. (a) Explain, How error occurred in a data transmission can be detected usingparity bit. [6]
(b) Perform the subtraction with the following unsigned binary numbers by takingthe 2’s complement of the subtrahend. [5×2]
i. 111011 - 111000
ii. 1110-110110
iii. 10010-1101
iv. 110-10100
v. 11011-10000.
2. (a) Explain in detail, the various levels of integration in ICs.
(b) Obtain the Dual of the following Boolean expressions.
i. AB + A(B + C) + B’(B + D)
ii. A + B + A’B’C.
(c) Obtain the complement of the following Boolean expressions. [8+4+4]
i. A’B + A’BC’ + A’BCD + A’BC’D’E
ii. ABEF + ABE’F’ + A’B’EF.
3. (a) Implement the following Boolean expression with Excusive-NOR and NORgates:F = ABCD + ABCD + AB CD + ABCD
(b) If F1 = wxy+y z+wyz+xyz AndF2 = (w + x + y + z) (x + y + z) (w + y + z)Obtain minterms list of F1 •F2 using K-map obtain minimal SOP function ofF1 • F2. [8+8]
4. (a) A multiple output combinational logic circuit is defined by the following func-tions. Draw the schematic circuits for F1 and F2.
F1 (A,B,C,D) = A • AD •(A + BC
)F2 (A,B,C,D) = AD •
(A + BC
)Using K-Maps simplify F1 and F2 and draw the reduced diagram circuit.
(b) Design a full - subtractor circuit with three inputs x,y,z and outputs D, B.The circuit subtracts X - Y - Z where Z is the input borrow, B is the outputborrow and D is the difference draw the circuit using NAND gates. [8+8]
1 of 2
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Code No: X0524/R07 Set No. 3
5. (a) Define the following terms related to filp-flops.
i. set-up time
ii. hold time
iii. propagation delay
iv. preset and
v. clear.
(b) Distinguish between combinational logic and sequential logic. [10+6]
6. Design a circuit with three 4-bit registers A,B and C to perform the followingoperations.
(a) Transfer two binary numbers to A and B when a start signal is enabled,
(b) If A <B, shift left the contents of A and transfer the result to register C.
(c) If A >B, shift right the contents of B and transfer the result to register C.
(d) If A=B, transfer the number to register C unchanged.
Explain the procedure. [16]
7. (a) What is parity checking? Explain its necessity and how is it implemented?
(b) How many parity check bits must be included with the data word to achievesingle error-connection and double-error detection when the data contains
i. 16 bits
ii. 32 bits
iii. 48 bits. [8+8]
8. (a) Describe the operation of the SR Latch using NAND gate with the help oftruth table, transition table and the circuit.
(b) Explain the operation and use of De bounce circuit. [8+8]
? ? ? ? ?
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Code No: X0524/R07 Set No. 4
II B.Tech I Semester Supplementary Examinations, November 2012DIGITAL LOGIC DESIGN
( Common to Computer Science & Engineering, Information Technologyand Computer Science & Systems Engineering)
Time: 3 hours Max Marks: 80Answer any FIVE Questions
All Questions carry equal marks? ? ? ? ?
1. (a) Generate Hamming code for the given 11 bit message 11001001100 and rewritethe entire message with Hamming code.
(b) The binary numbers listed have a sign bit in the left most position and , if neg-ative numbers are in 1’s complement form. Perform the arithmetic operationsindicated and verify the answers. [8+8]
i. 101011 + 111001
ii. 001111 + 110010
iii. 111001 - 011010
iv. 101111 - 100110.
2. (a) Express the following functions in sum of minterms and product of maxterms.
i. F (A,B,C,D) = B’D + A’D + BD
ii. F(x,y,z) = (xy + z)(xz + y).
(b) Obtain the complement of the following Boolean expressions.
i. (AB’ + AC’)(BC + BC’)(ABC)
ii. AB’C + A’BC + ABC
iii. (ABC)’(A + B + C)’
iv. A + B’C (A + B + C’). [8+8]
3. (a) With the use of map obtain minimal SOP expression for the function F3 =F1 • F2 Where F1 and F2 are shown below:F1 = ABC + CD + ACD + BCD
F2 =(A + B + C + D
) (B + C + D
) (A + C + D
)(b) Use K - map to obtain minimal SOP expression for the function given below
and draw the circuit using NOR - gates.F (A,B,C,D) = ABC + ABC + ABC + A BC + CD + AB + ABCD
4. (a) Design a code converter to convert 8421 code to excess - 3 code.Consider all invalid combinations, as don’t cares. Draw the circuit using onlyNAND gates.
(b) A Boolean function is defined as follows. Draw schematic circuit for the givenfunction F. Using K-map obtain its minimal SOP expression and draw thereduced diagram.F =
(A + BC
)+(AB ⊕D
)[8+8]
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Code No: X0524/R07 Set No. 4
5. (a) Explain the following terms related to filp-flops.
i. race round conditions
ii. propagation delay
iii. clock.
(b) Explain the operation of R-S flip-flop with negative edge triggering with neatsketch. And explain its truth table. [8+8]
6. Draw the sequential circuit for serial adder using shift registers, full adder andD-FF. Explain its operation with state equations and state table . [16]
7. (a) Give the HDL code for a memory read, write operations if the memory size is64 words of 4 bits each. Also explain the code.
(b) A 16K * 4 memory uses coincident decoding by splitting the internal decoderinto X-selection and Y-selection. [8+8]
i. What is the size of each decoder and how many AND gates are requiredfor decoding the address?
ii. Determine the X and Y selection lines that are enabled when the inputaddress is the binary equivalent of 6,000.
8. (a) Describe the analysis procedure of asynchronous sequential logic using flowtable.
(b) Obtain a primitive flow table for a circuit with two inputs, x1 and x2 and twooutputs z1 and z2, which satisfy the following four conditions:
i. When x1x2 = 00, the output z1z2 = 00
ii. When x1 = 1 and x2 changes from 0 to 1, the output is z1z2 = 01
iii. When x2 = 1 and x1 changes from 0 to 1, the output is z1z2 = 10.