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Code No: T0102/R05 Set No. 1

II B.Tech II Semester Supplementary Examinations, April 2010STRENGTH OF MATERIALS-II

(Civil Engineering)Time: 3 hours Max Marks: 80

Answer any FIVE QuestionsAll Questions carry equal marks

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1. At a point is an elastic material, the resultant stress on a certain plane is 60MPa(tensile) inclined at 300 to the normal to that plane. On a plane at right angles tothis plane, there is a normal tensile stress of 42MPa. Find the principal stressesand locate the principal planes. Find also the max shear stress and the planes onwhich it acts. [16]

2. A spring loaded safety valve of 50mm dia. is to work against a boiler pressure of8N/mm2. Determine the lift of the valve when the mean dia. of spring is 160mm,number of turns 10 and wire dia. 20mm. Take N = 9× 104 N/mm2. [16]

3. An R.S.Tee-section, 150mm wide × 75mm deep, thickness of flange 9mm, thicknessof web 8.4mm, is used as a strut, 3 metre 4 long, ends hinged.Calculate the safeaxial load by Rankines formula, using a factor of safety of 3. Rankines constants,fc = 315N/mm2; a = 1/ 7500. [16]

4. A locomotive coupling rod of length 3m, rectangular section 60mm wide and 120mmdeep. It is subjected to an axial thrust of 120kN and a transverse u.d.l of 5kN/m.Assuming the hinged to be hinged and taking E = 200GN/m2 find the max valuesof deflection, B.M. and stress. [16]

5. A cylindrical chimney shaft of a hollow circular section, 2.50 metres external di-ameter, 1 metre internal diameter, is 30 metres high. If the horizontal intensityof wind pressure varies as X2/3 where X is the vertical height above the ground,calculate the overturning moment at the base due to the force of wind pressure,taking the coefficient of wind-resistance as 0.6. Given that the horizontal intensityof wind pressure at a height of 20 metres is 1KN/m2. If the weight of masonry is22.5KN/m3, calculate the extreme intensities of stress at the base. [16]

6. A simply supported beam of rectangular section (60×80)mm carries a load of 2KNat the center of 4m span. The load line is inclined at 30 to the vertical passingthrough the c.g. of section. Determine the max deflection and stress at the topcorner. (E = 210KN/mm2). [16]

7. A semi circular beam is supported on three equally spaced columns. Derive ex-pressions for max.B.M. and max. Twisting moment by first obtaining the generalexpressions. [16]

8. Using the method of joints find out the forces in all the members of the simply-supported pin-jointed plane truss loaded as shown in figure 1. [16]

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Figure 1:

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1. Calculate the dia of a steel rod according to max. shear stress theory if it has towith stand an axial pull of 10 kN and a transverse shear of 6 kN. The elastic limitin tension is 240 MPa and the factor of safety 3. [16]

2. A solid steel shaft is subjected to a B.M. of 500 kN m and a torque of 250 kN m.Find the dia. of the shaft according to

(a) Max. principal stress theory

(b) Max. strain theory

if the yield stress = 300N/mm2 factor of safety = 3 & 1

m= 0.3 [8+8]


4. (a) What do you understand by “Beam-columns”?

(b) A horizontal strut of length L, having hinged ends, carries an axial compres-sive load P, and central vertical load W. Derive expression for max values ofdeflection, B.M. and stress. [4+12]

5. A cylindrical chimney shaft of a hollow circular section, 2.50 metres external di-ameter, 1 metre internal diameter, is 30 metres high. If the horizontal intensityof wind pressure varies as X2/3 where X is the vertical height above the ground,calculate the overturning moment at the base due to the force of wind pressure,taking the coefficient of wind-resistance as 0.6. Given that the horizontal intensityof wind pressure at a height of 20 metres is 1KN/m2. If the weight of masonry is22.5KN/m3, calculate the extreme intensities of stress at the base. [16]

6. A simply-supported beam of T-section (100 × 150 × 20mm) carries a load P atcenter of 2.5m span. The load line is inclined at 30’ to the vertical and passesthrough c.g If the max. Compressive stress is not to exceed 75N/mm2, and themax tensile stress is not to exceed 35N/mm2, find the max load P which the beancan carry. [16]

7. A semi circular beam is supported on three equally spaced columns. Derive ex-pressions for max.B.M. and max. Twisting moment by first obtaining the generalexpressions. [16]

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8. Using the method of section find out the forces in all the members of the simply-supported pin-jointed plane truss loaded as shown in figure 1. [16]

Figure 1:

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1. At a point is an elastic material, the resultant stress on a certain plane is 60MPa(tensile) inclined at 300 to the normal to that plane. On a plane at right angles tothis plane, there is a normal tensile stress of 42MPa. Find the principal stressesand locate the principal planes. Find also the max shear stress and the planes onwhich it acts. [16]

2. Calculate the max. direct stress and max. shear stress for a shaft subjected tocombined bending and torsion at a certain section; B.M. = 6 kN-m and T.M. =8kN-m. If the Poisson’s ratio = 0.3, find the stress which acting alone will producethe same

(a) max. Strain and

(b) max. strain energy. [8+8]


4. A locomotive coupling rod of length 3m, rectangular section 60mm wide and 120mmdeep. It is subjected to an axial thrust of 120kN and a transverse u.d.l of 5kN/m.Assuming the hinged to be hinged and taking E = 200GN/m2 find the max valuesof deflection, B.M. and stress. [16]

5. Find the max. and minimum stress intensities at the weakest section of a flatbar 200mm wide and 30mm thick carrying an axial pull of 240kN. A 40mm dia.Hole is punched at a distance of 60mm from the axis of the bar. Sketch the stressdistribution. [16]

6. (a) What do you understand by centroidal principal axes and principal momentsof inertia.

(b) Determine the principal moments of inertia for an unequal angle section 80×60× 10mm. [8+8]

7. A semi circular beam of radius R, is supported on 3 equally spaced columns. If Wis the load per unit length of the beam, derive expressions for B.M and twistingmoments at any point P. and hence at supports. [16]

8. Using the method of sections find the forces in all the members of the cantilevertruss loaded as shown in figure 1. [16]

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Figure 1:

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1. (a) Explain the terms principal stresses and principal planes.

(b) Derive expressions for principal stresses, principal planes and max shear stressif there are like direct stresses accompanied by a state of simple shear. [6+10]

2. Calculate the max. direct stress and max. shear stress for a shaft subjected tocombined bending and torsion at a certain section; B.M. = 6 kN-m and T.M. =8kN-m. If the Poisson’s ratio = 0.3, find the stress which acting alone will producethe same

(a) max. Strain and

(b) max. strain energy. [8+8]


4. (a) What do you understand by “Beam-columns”?

(b) A horizontal strut of length L, having hinged ends, carries an axial compres-sive load P, and central vertical load W. Derive expression for max values ofdeflection, B.M. and stress. [4+12]

5. A short hollow cylindrical C.I. Column is 240 mm external and 180 mm internaldiameter. In casting, the bore got eccentric so that the thickness varies from 20mmat one end to 40 mm at the other. If the column carries a load of 600 KN along theaxis of the bore, calculate the extreme intensities of stress induced in the section.

[16]

6. A steel cantilever beam of rectangular section (60 × 40mm) projects horizontallybeyond the support by 500mm. The load face of the section makes an angle of 300

with the horizontal. A load of 200 N is hung at the free end. The vertical load linepasses through the c.g. of the section. Find the horizontal and vertical deflectionsand max tensile stress (E = 200KN/mm2) . [16]

7. A semi circular beam of radius R, is supported on 3 equally spaced columns. If Wis the load per unit length of the beam, derive expressions for B.M and twistingmoments at any point P. and hence at supports. [16]

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Figure 1:

8. Find the forces in all the members of the pin-jointed, simply-supported, plane frameloaded as shown in figure 1 by the method of joints make the magnitude and natureof forces in the frame. [16]

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II B.Tech II Semester Supplementary Examinations, April 2010ELECTRICAL MACHINES-II

(Electrical & Electronic Engineering)Time: 3 hours Max Marks: 80


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1. (a) What is stepping of transformer core? Why transformer cores are stepped?Generally how many stepped core is used for power transformers. What is theideal shape of core?

(b) The no load current of a transformer is 5 A at 0.25 pf, when supplied at235 V, 50 Hz. The number of turns on primary winding is 200. Calculatethe maximum value of flux in the core, the core loss, the magnetising & losscomponent of current. [8+8]

2. (a) Why it is essential to calculate all day efficiency for distribution transformers.How it is different from full load efficiency.

(b) A 20 kVA transformer has maximum efficiency of 98% when delivering 75%load at 0.95 pf. If during the day transformer is delivering load as follows, findthe all day efficiency of transformer. [6+10]

12 hours No load6 hours 12 kW, 0.8 pf6 hours 20 kW at upf.

3. (a) Explain the various simple tests conducted on a single transformer to find theapproximate equivalent circuit of transformer.

(b) OC test is preferred to conduct on LV side & SC test is preferred to conducton HV side. Explain the reasons. [10+6]

4. (a) With neat phasor diagram, explain the voltage regulation of three-phase trans-former.

(b) An ideal 3-Φ step down transformer connected in delta/star delivers powerto a balanced 3-Φ load of 120 kVA at 0.8 pf. The input line voltage is 11kV and the turn’s ratio of transformer (phase to phase) is 10. Determine theline voltage line currents, phase voltages, phase currents on both primary &secondary sides. [8+8]

5. (a) A 4 pole, wound rotor induction motor is used as a frequency changer. Thestarter is connected to a 50 Hz, 3-Φ supply. The load is connected to the rotorslip rings. What are the possible speeds at which the rotor can supply powerto this load at 25 Hz? What would be the ratio of voltages at load terminalsat these speeds? Neglect rotor impedance.

(b) Explain the construction of Slip ring IM. [8+8]

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6. (a) Explain the effect of load on performance of IM. How the operating range ofIM can be improved.

(b) The power supplied to a 3-Φ IM is 40 kW and the corresponding stator lossesare 1.5 kW. Calculate: total mechanical power developed rotor copper loss &efficiency when the slip is 4 %. [8+8]

7. With neat diagram explain the various tests to be conducted on 3-Φ IM to plot thecircle diagram. [16]

8. Compare various methods of speed control of 3-Φ IM. [16]

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1. (a) Draw the phasor diagram of a practical transformer ‘On load’ & explain cor-responding calculations.

(b) A 50 kVA single phase transformer has 500 turns on the primary & 100 turnson the secondary. The primary is connected to 3500 V, 50 Hz supply. Calculatethe following:

i. The secondary voltage

ii. The current flowing in the windings on full load

iii. The maximum value of flux. [8+8]

2. (a) Derive the condition for maximum efficiency of a transformer.

(b) A single phase 150 kVA transformer has efficiency of 96 % at full load, 0.8 pfand at half load, 0.8 pf lagging. Find maximum efficiency of transformer andcorresponding load. [8+8]

3. (a) Explain the disadvantages of OC & SC tests. How these disadvantages canovercome by Back to back test.

(b) Two single phase transformers A & B of ratings 500 kVA & 250 kVA aresupplying a load of 750 kVA at 0.8 pf lagging. Their OC voltages are 405 Vand 410 V respectively. Transformer A has 1 % resistance and 5 % reactance.Transformer B has 1.5 % resistance & 4 % reactance. Find circulating currentat no load and current supplied by each transformer and kVA shared by eachtransformer. [6+10]



5. (a) Explain the classification of induction motors based on construction of rotor.Explain the advantages & disadvantages of each.

(b) A 6 pole IM is connected to 440 V, 50 Hz, 3-Φ supply runs at 960 rpm.Calculate the synchronous speed and the percentage slip. [8+8]

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6. (a) What do you mean by the maximum torque of IM? What are the quantitiesinfluence maximum torque? Can you vary maximum torque of IM? If yes;how? If not, why Maximum torque of IM can not be varied?

(b) A 3-Φ, 440 V, 4 pole, 50 Hz, IM has star connected stator and rotor. Therotor resistance & standstill reactance/ph are 0.22 Ω & 1.2 Ω respectively, thestator to rotor turns being 1.3. The full load slip is 4 %. Calculate the full loadtorque & power developed. Find also the maximum torque & correspondingspeed. [8+8]

7. (a) Determine approximately the staring torque of IM in terms of full load torquewhen started by means of

i. Star delta starter

ii. Auto transformer starter with 50 % tapping.

Ignore the magnetising current. The short circuit current of the motor atnormal voltage is 6 times the full load current and full load slip is 4 %.

(b) Explain the advantages & disadvantages of auto transformer starter over stardelta starter. Why auto transformer starters are preferred for high power IMs.

[8+8]

8. Explain all the modes of operation of Induction machine. Plot the neat character-istics. [16]

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1. (a) With neat phasor diagram explain the operation of transformer with capacitiveload

(b) The voltage ratio of single phase 50 Hz transformer is 5000/500 V at no-load.Calculate the number of turns in each winding, if the value of the flux in thecore is 7.82 mWb. [8+8]

2. (a) Derive the condition for maximum efficiency of a transformer.

(b) A single phase 150 kVA transformer has efficiency of 96 % at full load, 0.8 pfand at half load, 0.8 pf lagging. Find maximum efficiency of transformer andcorresponding load. [8+8]

3. With neat diagram, explain the various tests conducted on transformer to obtainits equivalent circuit. Derive all related equations. [16]



5. (a) A 3-Φ, 4-pole, 50 Hz IM has a slip of 4%. Determine:

i. Synchronous speed

ii. Frequency of rotor currentsIf the rotor has a resistance of 1 Ω and standstill reactance of 4 Ω, calculatethe power factor at standstill and at speed of 1400 RPM.

(b) What is slip? How the slip affects the operation of IM? What is unit of slip?[8+8]

6. (a) Explain term Maximum torque, Full load torque, Starting torque & No-loadtorque.

(b) An 8-pole, 50 Hz, 3-Φ slip ring IM has effective resistance of 0.08 Ω/phase.The speed correspond to maximum torque is 650 rpm. What is the value ofresistance to be inserted in rotor circuit to obtain maximum torque at starting?[8+8]

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7. (a) A 4 pole, 3-Φ, 50 Hz, IM has a starting current which is 5 times its full loadvalue when switched on directly. What will be the % reduction in startingtorque if the motor is started with

i. with star-∆ starter

ii. Auto transformer starter with 65 % tapping.

(b) What are the specific advantages of rotor resistance starter over any othertype of starter? What is the reason that rotor resistance starters are limitedin use? [8+8]

8. (a) Explain the cascade connection operation for speed control of 3-Φ IM.

(b) Two 50 Hz, 3-Φ IM having 8 & 4 poles respectively are connected in cumulativecascade of which the 8 pole motor is connected to mains supply. Calculate therotor frequency & and slip of each motor referred to respective stator fields ifthe set has a slip of 5 %. [8+8]

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1. (a) Explain the operation of Ideal transformer. Draw the related phasor diagram.

(b) The cross section of a 4 kVA, 5000/500 V, 50 Hz single phase transformerhaving maximum flux density of 1.5 Tesla is 500 cm

2. Determine: Primary &secondary turns, the EMF per turn. Stacking factor is 0.95. [8+8]

2. (a) What is energy efficiency of transformer? Why energy efficiency of transformeris also important specification along with voltage regulation of transformer?Which types of transformers are specified with energy efficiency?

(b) A 50 MVA transformer with tap changer has percentage impedance of 0.5 +j 7.0 Ω. What tapping (in %) must be used to maintain the rated voltage atthe secondary on full load 0.8 pf lagging & 40 MVA at 0.9 lagging? [8+8]

3. With neat diagram, explain the various tests conducted on transformer to obtainits equivalent circuit. Derive all related equations. [16]



5. (a) A 3-Φ, 6-pole, 50 Hz IM has a slip of 1 % at no load & 4 % at full load.Determine:

i. Synchronous speed

ii. No-load speed

iii. Full load speed

iv. Frequency of rotor currents at standstill, at no load & at full load.

(b) Compare cage & wound rotors in terms of construction, performance & appli-cations. [8+8]

6. Derive the torque equation of IM. From this; derive the condition for Maximumtorque. Find the ratio of Maximum torque to Full load torque & Maximum torqueto staring torque. [16]

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7. (a) A 3-Φ, 4 pole, 50 Hz, 208 V IM has a stating line current of 70 A & a startingtorque of 225 Nm. If a reduced voltage of 120 V is applied to the stator atthe time of staring find starting torque & starting line current.

(b) Explain the advantages & dis-advantages of rotor resistance starter on anyother type of starters? 8+8]

8. Explain all the modes of operation of Induction machine. Plot the neat character-istics. [16]

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Code No: V0302/R05 Set No. 1

II B.Tech II Semester Supplementary Examinations, April 2010MECHANICS OF FLUIDS

( Common to Mechanical Engineering, Metallurgy & Material Technologyand Automobile Engineering)

Time: 3 hours Max Marks: 80Answer any FIVE Questions

All Questions carry equal marks? ? ? ? ?

1. (a) Expain briefly the following mechanical gauges:

i. Bourdon tube pressure gauge, and

ii. Diaphragm gauge.

(b) Distinguish between a Newtonian and non-Newtonian fluid

(c) What are manometers? [8+4+4]

2. (a) Find the velocity and acceleration at a point (1,2,3) after 1 sec. for a three-dimensional flow field given byu = yz + t, v=xz-t, w=xy, m/s

(b) State the conditions for a three-dimensional flow to be irrotational. [10+6]

3. (a) Prove that in case of forced vertex the rise of liquid level at the ends is equalto the fall of liquid level at the axis of rotation.

(b) An open circular cylinder of 15 cm diameter and 100cm long contain water upto a height of 80cm. Find the maximum speed at which the cylinder is to berotated about its vertical axis so that no water spills. [7+9]

4. (a) Differentiate Notches and Weirs and classify the Notches?

(b) The Coefficient of discharge for a venturimeter used for measuring the flowof an incompressible fluid was found to be constant when the rate of flowexceeded a certain volume. Show that under these conditions the loss of headhf in the convergent portion of venturimeter can be expressed as K1Q

2. WhereK1 is a constant. [7+9]

5. (a) Explain the effect of pressure gradient on boundary layer separation.

(b) In a stream of oil of specific gravity 0.85 and kinematic viscosity 0.82 stokes,a plate of 45 cm length and 25 cm width moving at 5 m/sec is placed parallelto the direction of motion. Determine [6+10]

i. boundary layer thickness at the trailing edge of the plate

ii. shear stress at trailing edge of the plate and

iii. frictional drag on one side of the plate.

6. (a) What do you mean by ‘pipes in series’? When pipes are connected in series?What is the loss of head in the system?

(b) A pipe system consists of three pipes in series [8+8]

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i. 300 m long, 150 mm in diameter,

ii. 150 m long, 100 mm in diameter and

iii. 250 m long, 200 mm in diameter. Determine the equivalent length of a125 mm diameter pipe. Take friction factor, 4f = 0.02 and coefficient ofcontraction, Cc = 0.6.

7. (a) What do you meant by viscous flow? Mention various forces to be consideredin Navier Stroke’s equation.

(b) Through a horizontal circular pipe of diameter 100 mm and of length 10m,an oil of dynamic 0.097 poise and relative density 0.9 is flowing. Calculatethe difference of pressure at the two ends of the pipe, if 100 Kg. of the oil iscollected in a tank in 30 seconds. [10+6]

8. (a) Derive the expression for the stagnation pressure?

(b) Calculate the Mach number of an object traveling at a 300m/s in an envi-ronment of air at 200K.estimate also corresponding stagnation temperature.Take K=1.4 and R=287 J/Kg.K. [8+8]

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1. (a) Expalin how the meta-centric height of a floating body can be detaerminedexperimentally?

(b) How are manometers are classified? [8+8]

2. (a) Velocity for a two dimensional flow field is given byV = (3+2xy+4 t2)i+(x y2+3t)jFind the velocity and acceleration at a point(1,2) after 2 sec

(b) Define tangential and local accelerations [10+6]

3. (a) Write shorts notes on:

i. Bernoulli’s equation

ii. Euler’s equation

iii. Vertex Flow.

(b) A closed vertical cylinder 350mm in diameter and height 400mm height is filledwith oil of relative density 0.9 to a depth of 280mm, the remaining volumecontaining air at atmosphere pressure. The cylinder rotates about its verticalaxis at such a speed that the oil. Just begins to uncover the base. Calculatethe speed of rotation for this condition. [6+10]

4. (a) Discuss the relative merits and demerits of venturimeter with respect to orificemeter

(b) A rectangular channel 6mts wide carries 2800 lit/sec at the depth of 0.9mts.What height of a broad crested rectangular weir must be installed to doublethe depth? Assume a weir co coefficient as 0.86. [7+9]

5. (a) Explain with a neat sketch the boundary layer characteristics when a fluid isflowing over a flat plate.

(b) A thin flat plate 0.3 m wide and 0.6 m long is suspended and exposed parallelto air flowing with a velocity of 3 m/sec. Calculate drag force on both sidesof the plate when the 0.3 m edge is oriented parallel to free stream. Considerflow to be laminar and assume for air kinematic viscosity is 0.18 stokes anddensity is 1.2 kg/m3. [10+6]

6. (a) What are the causes of loss of energy in pipe bends? Give expression to findloss of energy in pipe bends.

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(b) Particulars of three pipes connected in series are given below. [8+8]

Pipe Length(m) Diameter(mm) Friction coeeficient (4f)A 100 100 0.02B 120 75 0.028C 90 60 0.032

Find the size of a pipe of length 310 m whose pipe friction coefficient 4f = 0.024equivalent to the compound pipe.

7. (a) Sketch the Reynolds apparatus and explain how the laminar flow can bedemonstrated with the help of this apparatus?

(b) Oil of absolute viscosity 1.5 poise and relative density 0.85 flows througha 30cm diameter pipe .If the head losses in a 3000M length of a pipe is20M.estimate the friction factor by assuming the flow to be laminar. [8+8]

8. (a) Derive Bernoulli’s equation for compressible flow undergoing adiabatic process?

(b) Find the Mach number when an aero plane is flying at 1100Km/hr throughstill air having a pressure of 7 N/ cm2 and temperature -50C. Wind velocitymay be taken as zero. Take R=287.14J/KgK. Calculate the pressure, tempand density of air at stagnation point on the nose of the plane. Take K=1.4.

[8+8]

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1. (a) Define kinematic viscosity and dynamic viscosity state its units.

(b) What is a Newtonian fluid?

(c) Define the term ‘pressure’.

(d) What is the difference between cohesion and adhesion? [6+4+2+4]

2. (a) The diameter of a pipe at the sections 1-1 and 2-2 are 200 mm and 300 mmrespectively. If the velocity of water flowing through the pipe at section 1-1 is4 m/s, find;

i. Discharge through the pipe, and

ii. Velocity of water at section 2-2

(b) Define steady, non-steady, uniform and non-uniform flows. [8+8]

3. The discharge of water through a pipe of diameters 40cm is 400 Lit /sec. If thepipe is bend by 1200 , find the magnitude and direction of the resultant force onthe bend. The pressure of flowing water is 29.43 N/cm2 [16]

4. (a) Explain the working principle of Venturimeter and Orifice meter?

(b) i. A broad crested weir of 50mts length, has 50cms height of water aboveits crest. Find the maximum discharge. Take Cd =0.6. Neglect Velocityof approach.

ii. If the velocity of approach is to be taken into consideration, find themaximum discharge when the channel has cross sectional area of 50m2 onthe upstream side. [7+9]

5. (a) Explain with a neat sketch the boundary layer characteristics when a fluid isflowing over a flat plate.

(b) A thin flat plate 0.3 m wide and 0.6 m long is suspended and exposed parallelto air flowing with a velocity of 3 m/sec. Calculate drag force on both sidesof the plate when the 0.3 m edge is oriented parallel to free stream. Considerflow to be laminar and assume for air kinematic viscosity is 0.18 stokes anddensity is 1.2 kg/m3. [10+6]

6. Two pipes each of length L and diameters D1 and D2 are arranged in parallel, theloss of head, when a total quantity of Q flows through them, being h1. If the pipesare arranged in series and the same quantity of water, Q, flows through them, theloss of head is h2. If D1 = 2D2, find the ratio of h1 and h2. Neglect minor lossesand friction factor, f, to be constant. [16]

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7. (a) What do you meant by viscous flow? Mention various forces to be consideredin Navier Stroke’s equation.

(b) Through a horizontal circular pipe of diameter 100 mm and of length 10m,an oil of dynamic 0.097 poise and relative density 0.9 is flowing. Calculatethe difference of pressure at the two ends of the pipe, if 100 Kg. of the oil iscollected in a tank in 30 seconds. [10+6]

8. (a) What is the function of wind tunnel?

(b) Dry air flows in a duct 30 cm inside diameter .A Pitot tube inserted in thedirection of flow measures 15cm water column in a manometer. The staticpressure is 5 cm water gauge above atmospheric pressure and the temperatureis 170C . Determine the velocity of air. Take atmospheric pressure as 10.5 N/cm2. [6+10]

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1. (a) Calculate the specific weight, specific mass, specific volume and specific gravityof a liquid having a volume of 6 m3 and weight of 44 kN.

(b) Distinguish between simple manometer and a differential manometer. [8+8]

2. Two velocity components are given in the following cases, find the third componentsuch that they satisfy the continuity equation.

(a) u = x3 + y2 + 2z2; v = −x2y − yz − xy;

(b) u = log (y2 + z2) ; v = log (x2 + z2) ;

(c) u = −2xyz

(x2+y2)2; w = y

(x2+y2)[16]

3. (a) State the momentum equation .How will you apply momentum equation fordetermining the force exerted by a flowing liquid on a pipe bend?

(b) A pipe of diameter 400mm carries water at a velocity of 25m/s. The pressureat the points A and B are given of 29.43 N/cm2 and 22.563 N/cm2 respectivelywhile the datum head at A and B are 28m and 30m. Find the loss of headbetween A and B. [8+8]

4. (a) Discuss the relative merits and demerits of venturimeter with respect to orificemeter

(b) A rectangular channel 6mts wide carries 2800 lit/sec at the depth of 0.9mts.What height of a broad crested rectangular weir must be installed to doublethe depth? Assume a weir co coefficient as 0.86. [7+9]

5. (a) Draw a neat sketch showing the variation of drag coefficient for a sphere withReynolds number and explain the salient features.

(b) A jet plane weighing 112.82 kN has a wing span of 9.6 m and wing area of15.8 m2. It flies at 350 km/hour at a steady level in still air. Find [8+8]

i. The lift coefficient

ii. The total drag on the wing taking coefficient of drag (CD) = 0.08

iii. Power required to maintain the airplane at this velocity Take density forair = 1.25 kg/m3

6. (a) What do you mean by ‘pipes in series’? When pipes are connected in series?What is the loss of head in the system?

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(b) A pipe system consists of three pipes in series [8+8]

i. 300 m long, 150 mm in diameter,

ii. 150 m long, 100 mm in diameter and

iii. 250 m long, 200 mm in diameter. Determine the equivalent length of a125 mm diameter pipe. Take friction factor, 4f = 0.02 and coefficient ofcontraction, Cc = 0.6.

7. (a) Explain the terms

i. Long pipes

ii. Inclined pipes

iii. Equivalent pipe.

(b) Two sharp ended pipes of diameters 50 mm and 100 mm respectively, eachof length 100m are connected in parallel between two reservoirs which have adifference of level of 10M.If the coefficient of friction for each pipe is (4f) 0.32,calculate the rate of flow for each pipe and also the diameter of a single pipe100m long which would give the same discharge ,if it were substituted for theoriginal two pipes. [10+6]

8. (a) Derive an expression for velocity of sound for an adiabatic process.

(b) Calculate Mach number at a point on a jet propeller aircraft, which is flyingat 900 Km/hr at sea level where air temperature is 150C. Take K=1.4 andR=287 J/Kg-K. [8+8]

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II B.Tech II Semester Supplementary Examinations, April 2010SWITCHING THEORY AND LOGIC DESIGN

( Common to Electronics & Communication Engineering and Electronics &Telematics)



1. (a) Perform the following using BCD arithmetic. Verify the result.

i. 127310 + 958710

ii. 776210 + 383810

(b) Convert the following. [8+8]

i. 97710 = ( )16

ii. 65710 = ( )8

iii. 75410 = ( )2

iv. 100116 = ( )10

2. (a) For the given Boolean function F=xy’z+x’y’z+w’xy+wx’y+wxy [8]

i. Draw the logic diagram

ii. Simplify the function to minimal literals using Boolean algebra.

(b) Obtain the Dual of the following Boolean expressions. [8]

i. AB’C+AB’D+A’B’

ii. A’B’C+ABC’+A’B’C’D

iii. ABCD+ABC’D’+A’B’CD

iv. AB+ABC’

3. (a) Design an SOP logic circuit, which will output a 1(logic High) whenever theinput binary equivalent of decimal 0,1,5,7,8,10,13,15,16,17,23,24and31.

(b) Draw the Karnaugh map to represent the following Boolean function.F= (BD + A). [12+4]

4. Design and implement a Binary to Gray converter. [16]

5. (a) List the PLA programming table for the BCD to excess-3 code converter.

(b) A ROM chip of 4,096 × 8 bits has two clip select inputs and operates froma 5-volt power supply. How many pins are needed for the integrated circuitpackage? Draw the block diagram of this ROM. [8+8]

6. (a) Compare synchronous & Asynchronous circuits

(b) Design a Mod-6 synchronous counter using J-K flip flops. [6+10]

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7. A clocked sequential circuit with simple input x and single output Z produce anoutput Z = 1 whenever the input x completes the sequence 1 0 1 1 and overlappingis allowed.

(a) Obtain its state - diagram.

(b) Obtain its minimal state - table and design the circuit with T - Flip-Flops.[8+8]

8. (a) For the given ASM chart, obtain equivalent state-diagram 1.

(b) Design the circuit using multiplexers. [8+8]

Figure 1:

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1. Convert the following to Decimal and then to Hexadecimal.

(a) 7448

(b) 15528

(c) 110110012

(d) 111100112

(e) 55710

(f) 73910 [3+3+3+3+2+2]

2. (a) Express the following functions in sum of minterms and product of maxterms.[8]

i. (xy+z) (y+xz)

ii. B’D+A’D+BD

(b) Obtain the complement of the following Boolean expressions. [8]

i. AB’C+AB’D+A’B’

ii. A’B’C+ABC+A’B’C’D

iii. ABCD+ABC’D’+A’B’CD

iv. AB+ABC’

3. (a) Write short note on prime implicant chart.

(b) Minimize following function using Tabular minimization.F (A, B, C, D) =

∑m(6, 7, 8, 9) + d(10, 11, 12, 13, 14, 15). [4+12]

4. (a) Implement the full adder function by using two 4:1 multiplexers.

(b) What is a decoder? How do you convert a decoder to a Demultiplexer.[10+6]

5. (a) Specify the size of a ROM (number of words and numbers bits per word) thatwill accommodate the truth table of a BCD to seven segment decoder with anenable input.

(b) Write a brief note on programmable logic devices. [8+8]



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7. A clocked sequential circuit is provided with a single input x and single output Z.Whenever the input produce a string of pulses 1 1 1 or 0 0 0 and at the end of thesequence it produce an output Z = 1 and overlapping is also allowed.

(a) Obtain State - Diagram.

(b) Also obtain state - Table.

(c) Find equivalence classes using partition method & design the circuit using D- flip-flops. [4+4+8]

8. (a) For the given ASM chart obtain its equivalent state diagram 1.

(b) Design the circuit using multiplexers.

(c) Also design the circuit using D-Flip-flop per state. [4+8+6]

Figure 1:

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1. A 12-bit Hamming code word containing 8-bits of data and 4 parity bits is read frommemory. What was the original 8-bit data word that was written in to memory if12-bit words read out is as follows. [4 ×4 = 16]

(a) 000011101010

(b) 101110000110

(c) 101111110100

(d) 110011010010

2. (a) Express the following functions in sum of minterms and product of maxterms.[8]

i. F(A,B,C,D)=B’D+’D+BD

ii. F(x,y,z)=(xy+z)(xz+y)

(b) Obtain the complement of the following Boolean expressions. [8]

i. (AB’+AC’)(BC+BC’)(ABC)

ii. AB’C+A’BC+ABC

iii. (ABC)’(A+B+C)’

iv. A+B’C(A+B+C’)

3. (a) Reduce the following function using K- map and implement it in AOI logic aswell as NOR logic F=

∏M(0, 1, 2, 3, 4, 7) [10]

(b) What do you mean by K-map? Name its advantages and disadvantages [6]

4. (a) Implement the following Boolean function using a 8:1 multiplexer considering‘C’ as the input and A,B,C as selection lines. f(ABCD) = AB +BD + BCD

(b) Draw the Gate level diagram of a Decimal to BCD encoder. [10+6]

5. Write a brief note on:

(a) Architecture of PLDs

(b) Capabilation and the limitations of threshold gates. [8+8]

6. (a) Design a sequence detector which detects 110010 Implement the sequencedetector by using D - type flipflops

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(b) Classify the required circuits into synchronous, asynchronous, clockmode, pulsemode with suitable examples. [8+8]

7. A clocked sequential circuit is defined by the following state - table:

(a) Find equivalence classes using partition method.

(b) Give proper assignment.

(c) And design the circuit using D -Flip-Flops. [4+4+8]

Present state Next state qv+1 Out put ZP.S qv x=0 x=1 x=0 x=1

A A E 1 0B A E 0 0C B F 0 0D B F 0 0E C G 0 1F C G 0 1G D H 0 1H D H 0 1

8. (a) Draw the ASM chart for the following state transistion, start from the initialstate T1, then if xy=00 go to T2, if xy=01 go to T3, if xy=10 go to T1, otherwise go to T3.

(b) Show the exit paths in an ASM block for all binary combinations of controlvariables x, y and z, starting from an initial state. [8+8]

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1. Convert the following to Decimal and then to Octal.

(a) 25716

(b) 19916

(c) 101100012

(d) 110011002

(e) 34410

(f) 76610 [3+3+3+3+2+2]

2. (a) Reduce the following Boolean Expressions [8]

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. [8]

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’

3. (a) Explain ,the determination of all possible minimal expressions from a reducedprime implicant chart. [8]

(b) Make a K-map of the following expression and obtain the minimal SOPandPOS forms. (AC) + (AB) + (C) + (AD) + (ABC) + (ABC). [8]

4. A circuit receives a 4-bit Excess-3 code. Design a minimal circuit to detect thedecimal numbers 0,1,4,6,7,and 8. [16]

5. Find the function f(x1, x2, x3, x4) realized by each of the threshold networks shownin the figure 1, 2, 3 show the map of each function. [16]



7. For the minimal state table:

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Figure 1:

Figure 2:

Figure 3:

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(a) Give proper Assignment.

(b) Design the circuit using D - Flip-Flops. [8+8]

Present State Next state out - putqv qv+1 Z

X=0 X=1A B,0 A,0B C,0 A,0C D,0 E,0D D,0 A,0E B,1 A,0

8. (a) For the given control state-diagram, draw the equivalent ASM chart.

(b) Design the control circuit using multiplexers for the above state diagram 4.[8+8]

Figure 4:

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II B.Tech II Semester Supplementary Examinations, April 2010DESIGN AND ANALYSIS OF ALGORITHMS

(Computer Science & Engineering)Time: 3 hours Max Marks: 80


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1. (a) Solve the recurrence relation, where N is an integer power of 3T(N) = 6T(N/3) + 2N− 1, n > 1 andT(N) = 2 , N = 1

(b) Differentiate between priori analysis and posteriori analysis.

(c) Show that n is 0(nlogn). [8+4+4]

2. (a) Write and explain the control abstraction for Divide and conquer.

(b) Suggest refinements to mergesort to make it in-place. [8+8]

3. (a) Prove that the Greedy algorithm always finds an optimal schedule.

(b) Explain the Kruskal’s algorithm with an example. [8+8]

4. (a) Using dynamic programming method, find the maximum no.of operation pos-sible for the following chain matrix multiplication and also the sequence ofmultiplications that will require this maximum no. of operationsA(20,30) * B(30,5) * C(5,12),* D(12,5)

(b) Define merging and purging rules in o/1 Knapsack problem. [10+6]

5. (a) A directed graph G=(V,E) is singly connected if u → v implies that there isatmost one simple path from u to v for all vertices u, v ∈ V. Give an efficientalgorithm to determine whether or not a directed graph is singly connected.

(b) Differentiate between BFS and DFS. [10+6]

6. (a) Draw and explain the solution space organization for the sum of subsets prob-lem using variable tuple size formulation with an example.

(b) Differentiate between Bruteforce approach and Backtracking. [10+6]

7. (a) Explain the method of reduction to solve TSP problem using Branch andBound.

(b) Explain the principles of FIFO Branch and Bound. [8+8]

8. (a) Write the Nondeterministic sorting algorithm. Also Analyze its complexity.

(b) Distinguish between deterministic and non-deterministic algorithms. [10+6]

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1. (a) Write an algorithm to find the largest of given ‘n numbers. Derive its timecomplexity.

(b) Differentiate between profilling and debugging. [10+6]

2. (a) Derive a time complexity of Quicksort in average case.

(b) Explain the divide and conquer method with an example. [8+8]

3. (a) Write a greedy algorithm to the Job sequencing with deadlines.

(b) Prove that the edge with the smallest weight will be part of every minimumspanning tree. [8+8]

4. (a) In how many ways, the following chain of matrices may be multiplied?A X B X C X D

[2X5] [5X3] [3X6] [6X4]

Find the no. of multiplications required in each case.

(b) Differentiate between Greedy method and Dynamic programming

(c) Define merging and purging rules of O/1 Knapsack problem. [6+5+5]

5. (a) Explain the properties of depth-first search.

(b) Write a non-recursive algorithm of Post-order traversal of a tree and alsoanalyze its time complexity. [6+10]

6. (a) Write an algorithm to generate next color in M coloring problem.

(b) Draw the tree organization of the 4-queen solution space. Number the nodesusing DFS. [8+8]

7. (a) Explain the general method of Branch and Bound.

(b) Explain the principles of LIFO Branch and Bound. [8+8]

8. (a) Explain the classes of P and NP.

(b) Write a nondeterministic Knapsack algorithm. [8+8]

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1. (a) Consider a polynomial in n of the form

f (n) =m∑

i=0

aini. = amnm + am−1n

m−1 + ..... + a2n2 + a1n + a0 where am > 0

then f (n) = Ω (nm)


2. Write and explain the divide and conquer mergesort algorithm? Also compute itstime complexity. [16]

3. (a) What is spanning tree? Explain the prim’s algorithm with an example.

(b) Explain the terms Feasible solution, optimal solution and objective function.[10+6]

4. Write a pseudocode of the dynamic programming algorithm for solving OptimalBinary search tree and determine its time and space efficiencies. [16]

5. (a) Find a necessary and sufficient condition for the root of a depth first searchfor a connected graph to be an articulation point. Prove it.

(b) Show that the inorder and postorder sequences of a binary tree uniquely definethe binary tree. [8+8]

6. (a) Let w = 20, 18, 15, 12, 10, 7, 5 and m=35. Find all possible subsets of w thatsum to m. Draw the portion of the state space tree that is generated.

(b) Describe the applications of m-coloring. [10+6]

7. (a) Explain the method of reduction to solve TSP problem using Branch andBound.

(b) Explain the principles of FIFO Branch and Bound. [8+8]

8. (a) Write the Nondeterministic sorting algorithm. Also Analyze its complexity.

(b) Distinguish between deterministic and non-deterministic algorithms. [10+6]

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1. (a) Consider a polynomial in n of the form

f (n) =m∑

i=0

aini. = amnm + am−1n

m−1 + ..... + a2n2 + a1n + a0 where am > 0

then f (n) = Ω (nm)


2. (a) Write and explain the control abstraction for Divide and conquer.

(b) Suggest refinements to mergesort to make it in-place. [8+8]

3. (a) Write Greedy algorithm to generate shortest path.

(b) If p1/w1 ≥ p2/w2......... ≥ pn/wn prove that knapsack generates an optimalsolution to the given instance of the knapsack problem. [8+8]

4. (a) Find one problem for which the principle of optimality does not hold. Explainwhy the principle does not hold.

(b) Find the shortest path between all pairs of nodes in the following graph.(Figure 1) [8+8]

Figure 1:

5. (a) Explain game tree with an example.

(b) Prove or disprove an undirected graph G=(V,E) is biconnected if and only iffor each pair of distinct vertices u and v there are two distinct paths from uto v that have no vertex in common except u and v. [8+8]

6. (a) Draw and explain the solution space organization for the sum of subsets prob-lem using variable tuple size formulation with an example.

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(b) Differentiate between Bruteforce approach and Backtracking. [10+6]

7. (a) What is Bounding? Explain how these bound are useful in Branch and Boundmethods.

(b) Describe the TSP in Branch and Bound. [8+8]

8. (a) Explain the satisfiability problem and write the algorithm for the same.

(b) Differentiate between NP-complete and NP-Hard. [10+6]

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II B.Tech II Semester Supplementary Examinations, April 2010CHEMICAL ENGINEERING THERMODYNAMICS-I

(Chemical Engineering)Time: 3 hours Max Marks: 80


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1. (a) List the methods of measuring the pressure. Discuss any one of them.

(b) Given that the standard atmospheric pressure is 101.325 kPa and the averagetop surface area of a human head is 3 × 10−2

m2, calculate the mass of air

which is exerting the pressure on a human head. [8+8]

2. (a) State the condition for thermal equilibrium between two given systems.

(b) How do we classify a process as reversible or irreversible? [8+8]

3. (a) What is non ideal gas? How it is different from ideal gas? Compare PV datafor ideal and non ideal gas.

(b) Define generalized compressibility factor Z. [10+6]

4. (a) Discuss throttling process in brief.

(b) Measurement of P and T does not give any information regarding the qualityof wet steam. Specify, why? [8+8]

5. Two Carnot engines A and B are connected in series between two thermal reservoirsat 1000K and 100K respectively. Engine A receives 1680 kJ of heat from the hightemperature reservoir and rejects heat to the Carnot engine B. Engine B takes inheat rejected by engine A and rejects heat to the low temperature reservoir. Ifengines A and B have equal thermal efficiencies, determine

(a) the heat rejected by engine B,

(b) the temperature at which heat is rejected by engine A [16]

6. Discuss the entropy changes of an ideal gas. Develop suitable equations. [16]

7. It is desired to maintain an auditorium at 220C throughout the year. For thispurpose, it is planned to use a reversible device as a refrigerator in summer anda heat pump in winter. The rate of energy losses as heat from the roof and wallsof the auditorium is estimated at 103kW per degree Celsius difference between theinside and outside temperature. If the outside temperature is 030C in winter and390C in summer, estimate the power required to operate the device in winter andin summer. [16]

8. (a) Suppose one kmol of an ideal gas (γ = 1.4) is allowed to undergo an adiabaticexpansion from 1MPa and 960 K to 301 K. Determine the work that can beobtained from the gas.

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(b) State the energy minimum principle. [10+6]

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1. (a) State relations between absolute, gauge, atmospheric and vacuum pressures.

(b) A mercury manometer is used to measure the pressure drop of water flowingin a pipe line. If the difference of the mercury levels in the two lines reads 15cm, determine the pressure drop. The density of mercury is 13.6 × 103 kg/m3

and that of water is 1 × 103 kg/m3. [6+10]

2. Compute the degrees of freedom if,

(a) System is made up of liquid water in equilibrium with its vapour and helium.

(b) System consists of liquid water and liquid touene (immiscible) in equilibriumwith its vapours.

(c) System is consisting of solid carbon, CO, CO2 and O2 in chemical equilibrium.[5+5+6]

3. Name the methods by which the thermodynamic properties of fluids are usuallypresented. Discuss any two of them. [16]

4. (a) List two idealizations that are impressed from the start to facilitate the appli-cation of thermodynamic principles to flow processes.

(b) Show that for a flow process. ∆ (ρUA)fs = 0. [6+10]

5. A reversible heat engine interacts with three reservoirs at 900K, 500K, and 300K. Itabsorbs 2850 kJ energy as heat from the reservoir at 900 K, rejects 2580 kJ energyas heat to the reservoir at 500 K. Determine the heat interaction with the reservoirat 300 K and the net work delivered by the engine. [16]

6. One kg of water at 273 K is brought into contact with a heat reservoir at 373 K.When the water has reached 373 K, find the entropy change of the water, of thereservoir, and of the universe. Specific heat of water is 4.187 kJ kg−1K−1. [16]

7. A household refrigerator is maintained at a temperature of 30C. Every time thedoor is opened, warm material is placed inside, introducing an average of 450kJ,but making negligible change in the temperature of the refrigerator. The door isopened 25 times a day, and the refrigerator operates at 20% of the ideal COP.The cost of the work is 1.20 rupees per kWhr. What is the monthly bill of therefrigerator? The atmosphere is at 320C. [16]

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8. Suppose one kmol of an ideal gas is available at 1MPa and at ambient temperatureof 301K. If the gas is allowed to expand to 0.11 MPa, while in contact with theambient atmosphere and the final temperature of the gas is same as the ambienttemperature, calculate the maximum work that can be obtained from the gas. [16]

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1. One mole of an ideal gas is initially at 103 kPa and 305 K. It is compressed atconstant pressure till the volume is reduced to one sixth of the original volume.Then it is compressed at constant volume till the pressure rises to six times theinitial pressure and allowed to expand at constant temperature to the originalconditions of 103 kPa and 305 K. Sketch the processes on a P- ϑ diagram andcalculate the total work done by the gas. [16]

2. Water flows over a water fall 107 m in height. Consider 1 kg of water, and assumethat no energy is exchanged between the 1 kg and its surroundings,

(a) What is the potential energy of the water at the top of the falls with respectto the base of the falls.

(b) What is the kinetic energy of the water just before it strikes bottom.

(c) After 1kg of water enters the river below the falls, what change has occurredin its state? [5+5+6]

3. (a) What is ideal gas? Name the two basic assumptions, which were made use ofin deriving the ideal gas equation of state from kinetic theory arguments.

(b) Define isothermal compressibility and coefficient of volume expansion. [10+6]

4. Discuss mechanical energy balance for flow processes. Develop Bernoulli equation.[16]

5. A reversible heat engine interacts with four reservoirs at 1000K, 600K, 400K and300K. It absorbs 2000 kJ energy as heat from the reservoir at 1000 K, rejects 600kJ energy as heat to the reservoir at 300 K and delivers 1200 kJ work. Determinethe energy interaction with the other two reservoirs. [16]

6. Discuss the mathematical statement of second law of thermodynamics. What areits conclusions? [16]

7. A cold storage is to be maintained at -60C, while the surroundings are at 330C.The heat leakage from the surroundings into the cold storage is estimated to be31kW. The actual COP of the refrigeration plant is one third that of an ideal plantworking between the same temperatures. Find the power required in kW to drivethe plant. [16]

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8. Tank A of volume 1m3 containing 5.2 k-mol of a gas at 590K is brought into contactthrough a dia-thermal wall with a tank B of volume 1m3 containing 3.2k-mol ofthe same gas at 410K. Determine the equilibrium temperature of the gas and theinternal energy of gas in tank A and B, if the gas obeys the equation of state1/T = 3NR

2U. [16]

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1. (a) What are usual units of expressing pressure? Show relations among them.

(b) At 270 C, the reading on a manometer filled with mercury is 60.5 cm. Thelocal acceleration of gravity is 9.784 ms−2. To what pressure does this heightof mercury correspond? [8+8]

2. One mole of an ideal gas at P1, T1 is allowed to expand reversibly and isothermallytill the pressure reduces to 60% of the original pressure followed by a constantvolume cooling till its pressure reduces to 30% of the original value. Than it isrestored to the initial state by a reversible adiabatic process. Calculate the networkdone by the gas. [16]

3. It is desired to design a tank to store 11 kmol methane at 5.8 MPa and 303 K.Determine the size of the tank using generalized compressibility chart. The criticalconstants of methane are Pc = 4.6 MPa and Tc = 190.6K. [16]

4. Write short notes on any two:

(a) Compressors,

(b) Pumps,

(c) Turbines. [16]

5. Two reversible heat engines A and B are arranged in series. A rejecting heat directlyto B. Engine A receives 207 kJ at a temperature of 4190C from a hot source, whileengine B is in communication with a cold sink at a temperature of 4.20C. If thework output of A is twice that of B, find

(a) the intermediate temperature between A and B

(b) the efficiency of each engine, and

(c) the heat rejected to the cold sink. [16]

6. If one kg of water is heated from 275 K to 375 K by first bringing it in contactwith a reservoir at 325 K and then with a reservoir at 375 K. In this way, water isheated from 275 K to 325 K and from 325 K to 375 K. Find the entropy change ofthe water, of the reservoir, and of the universe. Specific heat of water is 4.187 k Jkg−1K−1. [16]

7. (a) What is the importance of COP of a refrigerator? A Carnot refrigerator isoperating between two reservoirs at -200C and 400C. Determine the COP ofthe refrigerator.

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(b) Determine the COP of a Carnot heat pump operating between -200C and400C. [10+6]

8. A particular thermodynamic system has the following fundamental relation U =CS3

V N, where C is a constant. Transform the given fundamental relation into Helmholtz

free energy representation. [16]

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II B.Tech II Semester Supplementary Examinations, April 2010LINEAR IC APPLICATIONS

(Electronics & Instrumentation Engineering)Time: 3 hours Max Marks: 80


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1. (a) Discuss the differences between the differential amplifiers used in the first twostages of op - amp.

(b) Compare and contrast an ideal op - amp and practical op - amp.

(c) Draw an ideal voltage transfer curve of an op - amp. [8+5+3]

2. (a) An op - amp has a slew rate of 2V/µs. What is the maximum frequency of anoutput sinusoid of peak value 5 V at which the distortion sets in due to theslew rate limitation?

(b) What are the characteristics of an ideal op - amp and Explain. [8+8]

3. (a) Draw a neat circuit diagram of a.c non - inverting amplifier with single supply.Explain its working with its input output waveforms.

(b) For a non - inverting single supply AC amplifier Rin = 50Ω, Ci = 0.1µf, C1 =0.1µf, Rl = R2 = R3 = 100KΩ, RF = 1MΩ and Vcc = +15V. Determine thebandwidth of the amplifier and maximum output voltage swing. [8+8]

4. (a) Design a monostable multivibrator with trigger pulse shape which will drivean LED, ‘ON’ for 0.5 seconds each time it is pulsed.

(b) Derive the frequency of oscillation of a RC phase shift oscillator and explainthe operation of the circuit. [6+10]

5. (a) Design the band pass filter with fc = 1kHz,Q = 3,and AF = 10.

(b) Draw the frequency response and also change the center frequency to 1.5 kHzkeeping AF and band width content. [8+8]

6. Describe any two applications of 555 timer in

(a) Astable multivibrator configuration

(b) Monostable multivibrator configuration. [8+8]

7. (a) Compare R - 2R and weight resistor types of DACs.

(b) Write short notes on A/D converters.

(c) Define the following terms as related to DAC:

i. Linearity

ii. Resolution. [8+4+4]

8. (a) Explain different applications of multiplier circuits.

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(b) What is analog switch? Explain the different analog switches with suitablediagrams. [8+8]

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1. (a) Obtain differential mode gain of different configurations of differential ampli-fier using ac equivalent circuit.

(b) Explain how level shifter acts as buffer to isolate high gain stages from theoutput stage. [8+8]

2. (a) For the 741 IC op - amp, the supply voltage rejection ratio (SVRR) is 150µV/V.Calculate the change in this op - amp’s input offset voltage Vio if the supplyvoltages are varied from ±10V to ±12V.

(b) List and explain the characteristics of an ideal op - amp.

(c) Draw the pin diagram of µA741 op - amp. [4+8+4]

3. (a) Draw the circuit diagram of a two input non-inverting type summing amplifierand derive the expression for the output voltage.

(b) Briefly explain why negative feedback is desirable in amplifier applications.

(c) How does negative feedback affect the performance of an inverting amplifier?[7+5+4]

4. (a) Design a non - inverting comparator with output levels stabilizes at ± 5Vand VTL = 0 and VTH = 2.5V(TL: Lower threshold, TH: upper threshold) asshown in figure 1

(b) Describe the operation of antilog logarithmic amplifier. [8+8]

Figure 1:

5. (a) Explain the term “Frequency Sealing” with a suitable example.

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(b) Design a wide band-pass filter with fH=200Hz , fL=1KHz and a pass-bandgain=4. Draw the frequency response and calculate Q factor for the filter.

[6+10]

6. Describe any two applications of 555 timer in

(a) Astable multivibrator configuration

(b) Monostable multivibrator configuration. [8+8]

7. (a) Draw the circuit of Weighted resistor DAC and derive expression for outputanalog voltage, Vo.

(b) Explain the operation of the fastest analog to digital converter. What is themain drawback of this converter? Compare this converter with other types.

[6+10]

8. (a) Explain how multiplier can be used to modulate and demodulate an AM signal.

(b) What is meant by balanced modulator? Explain its function using neat dia-gram. [8+8]

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1. (a) Explain the operation of Dual input unbalanced output differential amplifier.

(b) Calculate V1 - V2 for the level shifter shown in figure 1. Assume identicalsilicon transistors with VBE = 0.7V and β = 1000.

(c) Name different configurations of differential amplifier. [8+4+4]

Figure 1:

2. (a) List the parameters that are important for ac applications?

(b) In an inverting amplifier of the type shown below figure 2 R1 = 100KΩ, Rf =10MΩ. Calculate maximum output offset voltage caused by the input offsetvoltage Vos; maximum output offset voltage caused by the input bias currentIB. The op - amp used is 741 with Vos = 6mv and IB = 500nA. [8+8]

3. (a) How the operational amplifier can be used as a differentiator and integrator.

(b) Explain how an operational amplifier can be used as summing amplifier.[8+8]

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Figure 2:

4. Design and explain a saw tooth waveform generator using operational amplifierand plot the waveforms for the given specifications frequency = 5kHz, Vsat = ±12Volts. [16]

5. (a) Classify the filters and explain the characteristics of each on of them.

(b) Draw the first order low - pass Butterworth filter and analyze the same byderiving the gain and phase angle equation. [8+8]

6. Explain the functional block diagram of PLL emphasizing the importance of Cap-ture range and Lock range. [6+5+5]

7. (a) Explain the operation of a Successive Approximation type analog to digitalconverter.

(b) Calculate the no. of bits required to represent a full scale voltage of 10V witha resolution of 5mV approximately. [10+6]

8. (a) Explain how multiplier can be used to modulate and demodulate an AM signal.

(b) What is meant by balanced modulator? Explain its function using neat dia-gram. [8+8]

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1. (a) What is meant by DC coupling?

(b) Discuss the operation of single ended input and unbalanced output differentialamplifier.

(c) Calculate V2 for the level shifter shown in figure 1. Assume identical silicontransistors with VBE = 0.705V and β = 100 and V1 of 12V. [4+8+4]

Figure 1:

2. (a) List the parameters that are important for ac applications?

(b) In an inverting amplifier of the type shown below figure 2 R1 = 100KΩ, Rf =10MΩ. Calculate maximum output offset voltage caused by the input offsetvoltage Vos; maximum output offset voltage caused by the input bias currentIB. The op - amp used is 741 with Vos = 6mv and IB = 500nA. [8+8]

3. (a) Design a practical integrator circuit to process the sinusoidal input waveformup to 1 KHz and the input amplitude is 10mv. Assume are necessary standardvalues of resistance.

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Figure 2:

(b) What are the different modes of operation of an active integrator? [8+8]

4. (a) What is a precision diode?

(b) Draw the circuit of a negative peak clamper and explain its operation withnecessary waveforms.

(c) Explain the functioning of a peak detector with necessary diagrams. [2+8+6]

5. (a) Explain the term “VSVS configuration”. Design a VCVS low pass Butterworthsecond order filter with a cutoff frequency of 4kHz. Assume necessary data inthe design process.

(b) What is meant by all pass filter? Draw the circuit of it. [10+6]

6. (a) Explain the functions of each of pins in 555 timer.

(b) List the important features of 555 timer. [8+8]

7. Compare and contrast the different types of integrating type Analog to Digitalconverter. [16]

8. (a) What is a switching regulator? Draw the block diagram of a typical switchingregulator and explain its operation.

(b) What are the four types of voltage regulators? Compare the performance ofthese regulators. [8+8]

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II B.Tech II Semester Supplementary Examinations, April 2010COMPUTER GRAPHICS

( Common to Information Technology and Computer Science & SystemsEngineering)



1. (a) How much time is spent in scanning across each row of pixels during screenrefresh on a raster system with a resolution of 1280 by 1024 and a refreshrate of 60 frames per second. Assume horizontal and vertical retrace times arenegligible.

(b) Discuss about the applications of computer graphics in the area of imageprocessing. [10+6]

2. (a) Explain the steps involved in scan-line polygon-fill algorithm. Illustrate withan example polygon and the corresponding sorted edge table.

(b) Explain the steps involved in [8+8]

i. odd-even rule and

ii. non-zero winding number rule, which are used for and carrying out inside-outside test.

3. (a) Describe the transformation which reflects an object about an arbitrary lineL.

(b) What is the relationship among rotation (Rθ) , inverse rotation (R−θ) and

coordinate rotation (R1

θ). [8+8]

4. (a) Draw the flow diagram or a brief step-wise procedure for implementing Sutherland-Hodgeman algorithm.

(b) Consider a convex polygon with n vertices being clipping against a clip rectan-gle. What is the maximum number of vertices is the resulting clipped window?What is the minimum number. [8+8]

5. (a) What are the steps involved in rendering a polygon surface mesh using Phongshading.

(b) Define the terms

i. geometric continuity

ii. parametric continuity. [8+8]

6. Prove that the multiplication of three-dimensional transformation matrices for eachof the following sequence of operations is commutative.

(a) Any two successive translations

(b) Any two successive saling operations

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(c) Any two successive rotations about any one of the coordinate axes. [16]

7. (a) What happens when two polygons have the same z value and the z-bufferalgorithm is used?

(b) For hidden surface removal of objects with non-planar surface, which algo-rithms (s) are suitable. Justify.

(c) What are the underlying concepts of the subdivision algorithm? [5+5+6]

8. (a) List and explain about the steps of animation.

(b) What are the various types of interpolation used in animation. [8+8]

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1. (a) Suppose we have a computer with 32 bits per word and a transfer rate of 1mip (one million instructions per second). How long would it take to fill theframe buffer of a 300 ? dpi (dot 8 per inch) laser printer with a page size of 81

2inches by 11 inches.

(b) Explain the applications of computer graphics in [10+6]

i. entertainment and

ii. education and training.

2. (a) Explain the steps involved in scan-line polygon-fill algorithm. Illustrate withan example polygon and the corresponding sorted edge table.

(b) Explain the steps involved in [8+8]

i. odd-even rule and

ii. non-zero winding number rule, which are used for and carrying out inside-outside test.

3. Determine the form of the transformation matrix for a reflection about an arbitraryline with equation y = mx+b. [16]

4. Explain the algorithm for line clipping by Cohen-Sutherland algorithm. Demon-strate with an example all the three cases of lines. [16]

5. (a) Define the B-spline geometry vector GBS and B-spline basis matrix MBS.

(b) Compute the B-spline blending functions. [8+8]

6. (a) Derive the generalized transformation matrix for rotation about an arbitraryaxis in three-dimensional domain.

(b) Derive the special cases correspond to rotation about

i. Coordinate z-axis

ii. Coordinate x-axis

iii. Coordinate y-axis. [8+8]

7. (a) Explain the possible relationships between polygon surfaces while implement-ing area-subdivision method. How to handle these cases.

(b) Illustrate with an example a scence consisting of three or more planes andexplain how the BSP tree is constructed to represent the scene. [8+8]

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8. (a) List and explain about the steps of animation.

(b) What are the various types of interpolation used in animation. [8+8]

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1. (a) How much time is spent in scanning across each row of pixels during screenrefresh on a raster system with a resolution of 1280 by 1024 and a refreshrate of 60 frames per second. Assume horizontal and vertical retrace times arenegligible.

(b) Discuss about the applications of computer graphics in the area of imageprocessing. [10+6]

2. (a) List the algorithm steps for ellipse generation using mid-point ellipse genera-tion.

(b) Explain how the interior and exterior regions are identified using odd partyrule. [8+8]

3. (a) Prove that a uniform scaling (sx = sy) and a rotation form a commutative pairof operations, but that, in general, scaling and rotation are not commutative.

(b) Derive the transformation matrix for rotation about origin. [8+8]

4. (a) Give a brief note about two dimensional viewing functions. Give an examplewhich uses two dimensional viewing functions.

(b) Explain the Cohen-Sutherland line clipping algorithm. [8+8]

5. (a) Describe the phong illumination model. Explain the parameters used inphong’s model.

(b) List and explain the problems with interpolated shading methods. [8+8]

6. Define tilting as a rotation about the x-axis followed by a rotation about the y-axis.If θx, θy are the rotations about x and y-axis.

(a) Find the tilting matrix

(b) Docs the order of performing the rotation matter. [16]

7. (a) Explain the depth-buffer (z-buffer) algorithm for hidden surface removal.

(b) Explain the procedure to compute the z-values in two successive locations ina scan-line and intersection positions on two successive scan lines. [8+8]

8. What are the steps in design of animation sequence? Describe about each stepbriefly. [16]

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1. List the operating characterstics of

(a) Raster refresh systems

(b) Vector refresh systems

(c) Plasma panel

(d) LCDs. [4×4=16]

2. (a) Explain the DDA scan conversion algorithm for generating the points on linesegment, when two end-points are given as input.

(b) Digitize the line with end-points (20,10) and (30,18) using DDA algorithm.[8+8]

3. Determine the form of the transformation matrix for a reflection about an arbitraryline defined with equation y = m x+b. [16]

4. (a) Give a brief note about two dimensional viewing functions. Give an examplewhich uses two dimensional viewing functions.

(b) Explain the Cohen-Sutherland line clipping algorithm. [8+8]

5. Explain the procedure to design two-dimensional cubic-Bezier curve shapes thathave second order piece-wise continuity. [16]

6. (a) How can scaling with respect to a point Po(xo, y

o, z

o) be defined in terms of

scaling with respect to the origin.

(b) Explain the step-wise procedure in aligning an arbitrary plane with one of theprincipal planes. [8+8]

7. (a) If the camera viewing direction is V and the surface normal of plane is N, howto determine whether the surface visible with respect to viewing direction ornot.

(b) Explain the depth-buffer method for elimination of hidden surfaces. [16]

8. Explain the procedure to generate the in-betweens for the key frames. [16]

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II B.Tech II Semester Supplementary Examinations, April 2010SIGNALS AND SYSTEMS

( Common to Electronics & Computer Engineering and Instrumentation &Control Engineering)



1. (a) Define orthogonal signal space and bring out clearly its application in repre-senting a signal.

(b) Obtain the condition under which two signals f1(t) & f2 (t) are said to beorthogonal to each other. Hence, prove that Sin nω0t and Cos mω0t areorthogonal to each other for all integer values of m,n. [6+10]

2. (a) With regard to Fourier series representation, justify the following statements.

i. Odd functions have only Sine term

ii. Even functions have no Sine terms

iii. Functions with half wave Symmetry have only odd harmonics. [3+3+3]

(b) Show that the Fourier series for a real valued signal can be written as

x (t) = B (0) +α∑

n=1

B (n) Cos (nωot) + A (n) Sin (nωot) where B(n) and A(n)

are real valued coefficients and express cn in terms of B(n) and A(n). [7]

3. (a) Distinguish between Fourier series and Fourier transform.

(b) State the conditions for the existence of Fourier transform of a signal.

(c) Find the Fourier transform of the signum function and plot it’s amplitude andphase spectra. [4+4+8]

4. (a) Explain how input and output signals are related to impulse response of a LTIsystem.

(b) Let the system function of a LTI system be 1

jw+2. What is the output of the

system for an input (0.8)t u (t). [8+8]

5. Find energies of the signals shown in figures 5a, 5b, 5c, 5d. Comment on the effectof on energy of sign change time shifting or doubling of the signal. What is theeffect on the energy if the signal is multiplied by K. [4×4]

(a)

Figure 5a

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(b)

Figure 5b

(c)

Figure 5c

(d)

Figure 5d

6. (a) A signal x(t)= 2 cos 400 π t + 6 cos 640 π t. is ideally sampled at fs = 500Hz.If the sampled signal is passed through an ideal low pass filter with a cut offfrequency of 400 Hz, what frequency components will appear in the output.

(b) A rectangular pulse waveform shown in figure 6b is sampled once every TS

seconds and reconstructed using an ideal LPF with a cutoff frequency of fs/2.Sketch the reconstructed waveform for Ts = 1

6sec and Ts = 1

12sec. [8+8]

Figure 6b

7. (a) Find the step response of series RLC circuits.

(b) Find the pulse response of series RL circuit figure 7b

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Figure 7b

(c) Find the pulse response of series RC circuit figure 7c [6+5+5]

Figure 7c

8. (a) Find the Z-transform of the following Sequences.

i. x[n] = a−n u[-n-1]

ii. x[n] = u[-n]

iii. x[n] = - an u[-n-1]

(b) Derive relationship between z and Laplace Transform. [8+8]

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1. (a) Define

i. Basis Functions

ii. Norm.

(b) Determine whether each of the following sequences are periodic or not. Ifperiodic determine the fundamental period.

i. x1(n) = sin(6π n/7)

ii. x2(n) = Sin (n/8)

(c) Consider the rectangular pulse x(t) of unit amplitude and a duration of 2 timeunits depicted in figure 1c. [8+4+4]

Figure 1cSketch y(t) =x(2t+3).

2. (a) Prove that Sinc(o)=1 and plot Sinc function.

(b) Determine the Fourier series representation of that Signal x(t) = 3 Cos(Πt/2+ Π/4) using the method of inspection. [6+10]

3. (a) Explain the concept of Fourier Transform for non-periodic signals.

(b) Find the Fourier Transform of the signal f(t) = te−at u(t), a >0. [8+8]

4. (a) Explain how Fourier Transform of input and output signals are related totransfer function of a LTI system.

(b) Let the system function of a LTI system be 1jw+2

. What is the output of the

system for an input (0.8)tu (t). [8+8]

5. (a) State and Prove Properties of cross correlation function.

(b) If V(f) = AT sin 2π fT/2π fT find the energy contained in V(t). [8+8]

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6. (a) Explain briefly impulse sampling.

(b) Define sampling theorem for time limited signal and find the nyquist rate forthe following signals. [8+8]

i. rect300t

ii. -10 sin 40πt cos 300πt.

7. (a) Determine the laplace transform of signal shown in figure 7a.

Figure 7a

(b) Find the step response of series RL circuit.

(c) Find the step response of series RC circuit. [6+5+5]

8. (a) Find the inverse Z-transform ofX(Z) = 2Z3

−5Z2+Z+3(Z−1)(Z−2)

|Z| < 1

(b) Find the inverse Z-transform of X(Z) = 3Z−2

|Z| > 2 .

(c) Find the Z-transform of an sin(nω)u(n). [6+4+6]

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1. (a) Sketch the following signals

i. Π(

t−1

2

)

+ Π(t− 1)

ii. f(t) = 3u(t) + tu(t)− (t− 1)u(t− 1)− 5u(t− 2)

(b) Evaluate the following Integrals [8+8]

i.5∫

0

δ(t)Sin2Πtdt

ii.α∫

−α

−αt2

e δ(t− 10)dt

2. (a) Write short notes on “Exponential Fourier Spectrum”.

(b) Find the Fourier series expansion of the periodic triangular wave shown figure2. [6+10]

Figure 2

3. Find the Fourier Transform of the following function

(a) A single symmetrical Triangular Pulse

(b) A single symmetrical Gate Pulse

(c) A single cosine wave at t=0 [8+4+4]

4. (a) Explain how input and output signals are related to impulse response of a LTIsystem.

(b) Let the system function of a LTI system be 1

jw+2. What is the output of the

system for an input (0.8)tu (t). [8+8]

5. (a) Show that∞∫

−∞

φ12(τ)dτ =

[

∞∫

−∞

f1(t)dt

] [

∞∫

−∞

f2(t)dt

]

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(b) Show that the cross correlation of any function f(t) with a unit impulse func-tion δ(t) yields the function f(t) itself. In general, show that the cross corre-lation of f(t) with δ(t− t0) is equal to f(τ + t0). [8+8]

6. (a) Define sampling theorem for time limited signal and find the nyquist rate forthe following signals.

i. sinc20t

ii. 4 sinc2100t.

(b) Discuss Natural sampling.

(c) Discuss effect of under sampling. [6+6+4]

7. (a) Determine the Laplace transform and the associate region convergence foreach of the following functions of time.

i. x(t) = 1 0 ≤ t ≤ 1

ii. x(t) =t 0 ≤ t ≤ 1

2− t 1 ≤ t ≤ 2

(b) State and prove initial value theorem of L.T. [10+6]

8. (a) Find the Z-transform X(n).

i. x[n] =(

1

2

)nu[n] +

(

1

3

)nu[n]

ii. x[n] =(

1

3

)nu[n] +

(

1

2

)nu[−n− 1]

(b) Find inverse z transform of x(z) using long division method [8+8]x(z) = 2 + 3z - 1

(1 + z - 1)

1 + 0.25 z - 1 -z - 2

8

!

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1. (a) Consider the pair of exponentially damped sinusoidal signalsx1 (t) = A eαtCos (ωt) t ≥ 0x2 (t) = A eαt sin (ωt) t ≥ 0

Assume that A, a and w are all real numbers,

the exponential damping factor α is negative and the frequency of oscillatorω is positive, the amplitude A can be positive or negative.

i. Derive the complex valued signal x(t) whose real part is x1(t) and imagi-nary part is x2(t).

ii. Determine a(t) for x(t) defined in part (i) where a(t) is envelope of thecomplex signal which is given bya (t) =

√

x21 (t) + x2

2 (t)

iii. How does the envelope a(t) vary with time t.

(b) Sketch the following signal x(t) = A[u(t+a) - u(t-a)] for a >0 Also determinewhether the given signal is a power signal on an energy signal or neither.

(c) State the properties of even and odd functions. [6+6+4]

2. (a) Prove that Sinc(o)=1 and plot Sinc function.

(b) Determine the Fourier series representation of that Signal x(t) = 3 Cos(Πt/2+ Π/4) using the method of inspection. [6+10]

3. (a) Determine the inverse Fourier transform of the spectrum shown figure 3a.

Figure 3a

(b) State and prove time convolution property of Fourier Transform. [12+4]

4. (a) Explain how Impulse Response and Transfer Function of a LTI system arerelated.

(b) Consider a stable LTI system that is characterized by the differential equationd2y(t)

dt2+4dy(t)

dt+3y (t) = dx(t)

dt+2x (t). Find its response for input x (t) = e−tu (t).

[4+12]

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5. (a) The waveform V(t)= e−t/Γ u(t) is passed through a high pass RC circuit havinga time constant Γ.

i. Find the energy spectral density at the output of the circuit.

ii. Show that the total output energy is one half the input energy.

(b) Find the cross correlation of the functions sin ωt and cos ωt. [8+8]

6. (a) What is aliasing? Explain its effect on sampling.

(b) State and prove sampling theorem. [8+8]

7. (a) Find inverse Laplace transform of the following:

i. s2+6s+7s2+3s+2

Re(s) > −1

ii. s3+2s2+6s2+3s

Re(s) > 0

(b) Find laplace transform of cos ωt. [8+8]

8. (a) Find the inverse Z-transform of

i. X(Z) = 1(1−az−1)2

|Z| > |a|

ii. X(Z) = 1(1−az−1)2

= z2

(z−a)2|Z| > |a|

(b) Find the Z-transform and the associated ROC for each of the following se-quences: [8+8]

i. x[n] = an+1u[n + 1]

ii. x[n] = a−nu[−n].

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II B.Tech II Semester Supplementary Examinations, April 2010THERMODYNAMICS

(Aeronautical Engineering)Time: 3 hours Max Marks: 80


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1. Air initially at 75 kPa pressure, 1000 K temperature and occupying a volume of0.12 m3 is compressed isothermally until the volume is halved and subsequently itundergoes further compression at constant pressure till the volume is halved again.Sketch the processes on p - V diagram and make calculations for the work done.

[16]

2. (a) A domestic refrigerator is loaded with food and the door closed. During acertain period the machine consumes 1 KW-hour of energy and the internalenergy of the system drops by 5000 KJ. Find the net heat transfer for thesystem.

(b) 1.5 kg of liquid having a constant specific heat of 2.5 KJ/kg-k is stirred ina well insulated chamber causing the temperature to rise by 150C. Find ∆Eand W for the process. [8+8]

3. (a) State the limitations of first law of thermodynamics.

(b) What is a thermal energy reservoir?

(c) An engine operating on a Carnot cycle works with in temperature limits of600 K and 300 K. If the engine receives 2000 KJ of heat, evaluate the workdone and thermal efficiency of the engine. [6+2+8]

4. (a) Explain the term dry ness fraction? [6M]

(b) One kg of steam at pressure of 20 bar and dryness fraction 0.85 is heated ata constant pressure to 3000C .Determine [10M]

i. Heated transferred

ii. Work done

iii. Change of internal energy

5. (a) Derive an expression for heat transfer in a non-flow constant volume process.[7M]

(b) A spherical shaped of 14 M diameter contain ’H2’ at 330C and 1.3 bar. Findthe mass of ’H2’ in the balloon using real gas equation. [9]

6. (a) Define

i. Partial pressure

ii. Mole fraction

iii. Volume fraction of a gas constituent in a mixture.

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(b) Air (N2 = 77%, O2 = 23%byweight)at250C and 12 bar is contained in a vesselof capacity 0.6m3 some quantity of CO2 is forced into the vessel so that thetemperature remains at 250C but the pressure rises to 18 bar. Find mosses ofO2, N2andCO2 in the cylinder. [6+10]

7. (a) Compare Carnot, Sterling and Ericsson cycles operating between the samesource and sink temperatures and with equal changes in specific volume.

(b) An engine working on Otto cycle has the following conditions: pressure at thebeginning of compression is 1 bar and pressure at the end of compressionis12 bar. Calculate the compression ratio and air - standard efficiency of theengine. Assume γ = 1.4. [8+8]

8. An ammonia rrefrigerating machine fitted with an expansion valve works betweenthe temp limited of −100 and 300. The vapour is 95% dry at the end of the ofisentropic compression and the fluid leaving the condenser is at 300C. Assumingactual C.O.P. as 60% of the theorectical, calculate the kgs of ice produced per kwhour at 00C from water at 100C. Latent heat of ice is 335kJ/kg. Ammonia has thefollowing properties: [16]

Temperature Liquid heat (hf ) Latent heat(hf g) Liquid entropy Total entropy dry0C kJ/kg kJ/kg Saturated vapour30 323.08 1145.80 1.2037 4.9842-10 135.37 1297.68 0.5443 5.4770

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1. (a) Write the differences between system and control volume.

(b) A gas undergoes a reversible non-flow process according to the relation P =(-3V+15)where V is the volume in m3 and P is the pressure in bar. Determinethe work done when the volume changes from 3 to 6 m3. [6+10]

2. (a) State the zeroth law of thermodynamics. Explain how it forms the basis fortemperature measurement?

(b) A closed system undergoes a thermodynamic cycle consisting of four separateand distinct processes. The heat and work transferred in each process are astabulated below.

Process Heat Transfer in KJ/min Work transfer in KJ/min1-2 20,000 02-3 -10,000 30,0003-4 0 20,0004-1 15,000 -25,000

Show that the data is consistent with the first law of thermodynamics. Also evaluatethe net work output in KW and the change in internal energy. [6+10]

3. (a) What are Helmholtz function and Gibbs function?

(b) 0.2 kg of air initially at 575 K temperature receives 300 KJ of heat reversibly atconstant pressure. Determine the available and unavailable energies of the heatadded. Take Cp for air = 1.005 KJ/Kg-K and temperature of surroundings300K. [6+10]

4. (a) Water vapour mixture at 1000C is contained in a rigid vessel of 0.5m3 capacitywater is now heated till it reaches critical state. What was the mass andvolume of water initially? [8]

(b) Steam turbine expands steam reversibly and adiabatic ally from 4mpa, 3000Cto500Catturbine exit, determine the work output per kg of steam. [8]

5. (a) Deduce the relation ship between absolute temperature and pressure in anpolytropic process. [7M]

(b) 0.3m3 of air at pressure 8 bars expands to 1.5m3 . The final pressure is 1.3bar. Assuming the expansion to be polytropic, calculate the heat supplied andchange of internal energy. Take γ= 1.4 [9]

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6. A 2.2 kg mole of Carbon dioxide at a presser of 2 bar, 800C is mixed in a thermallyinsulated vessel with 3.2 kg-mol of Nitrogen is at equilibrium; Determine the finaltemperature and pressure and the change in entropy of the mixture. [16]

7. (a) Explain graphically the variation of the efficiency of Diesel cycle with com-pression ratio and cut off ratio.

(b) A diesel engine has a compression ratio of 15 and heat addition at constantpressure takes place at 6% of stroke. Find the air standard efficiency of theengine. [8+8]

8. (a) Write the differences between refrigerator and heat pump? Deribe the COPfor both of them?

(b) The capacity of refrigerator is 280 tons. Determine the quantity of icec pro-duced at 00C with in 24 hours when water is supplied at a temperature of200C. [8+8]

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1. (a) How does classical thermodynamics differ from statistical thermodynamics ?

(b) A gas contained in a piston cylinder arrangement expands from 0.75 m3 volumeto 1.25 m3 volume while the pressure remains constant at 200 kPa. If thegaseous system receives 80 kJ of work from a paddle wheel, determine the network done by the system. [6+10]

2. (a) Write the steady flow energy equation and point out the significance of variousterms involved.

(b) Air at 1 bar pressure, 290 K temperature flows steadily at the rate of 120 m3/hrinto a compressor where its pressure and temperature are respectively raisedto 15 bar and 390 K. During the compression process, the heat transfer fromthe compressor is 10 percent of work transfer from the machine. Neglectingchanges in K.E and P.E., evaluate work and heat interactions. Take for airCp=1.005 KJ/Kg-K and R = 0.287 KJ/Kg-K. [6+10]

3. (a) Define the terms available energy and unavailable energy.

(b) 500 KJ of heat at constant temperature of 800 K was removed and suppliedto a system at constant temperature of 700 K. find the net loss of availableenergy as a result of this irreversible heat transfer. Take ambient temperatureas 300 K. [6+10]

4. (a) Define and explain the concept of triple point.? [6]

(b) Two boilers one with super heater and other without super heater are de-livering equal quantities of steam into a common main. The pressure in theboilers and main is 20 bar. The temperature of steam from a boilers witha super heater is 3500C and temperature of the steam in the main is 2500C.Determine the quality of steam supplied by the other boiler. Take Cp(steam)= 2.25 KJ/Kg.K [10]

5. (a) Deduce the relationship between absolute temperature and absolute pressurein an adiabatic process. [7]

(b) 1.5 kg of air at pressure 6 bar occupies a volume of 0.2m3.If this air is expandedto a volume of 1.1m3. Find the work done and heat absorbed or rejected bythe air for each of the following methods of trying one the process.

i. isothermally

ii. Adiabatic ally [9]

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6. (a) Explain

i. Saturated air

ii. Vapour presser

iii. Partial pressure

(b) Air(N2 = 77%, O2 = 23%byweight) at 200C and 10 bar is contained in avessel of capacity of 0.5m3. Some quantity of carbon dioxide is forced into thevessel so that the temperature remains at 200C but the pressure rises to15bar.Fined the masses of oxygen, nitrogen and carbon dioxide in the cylinder theuniversal gas constant 8.3143 Kj /kg. K. [6+10]

7. A gas engine operating on the ideal Otto cycle has a compression ratio of 6:1. Thepressure and temperature at the component of compression are 1 bar and 270C.

The heat added during the constant volume combustion process is 1170 kJ/kg.Determine the peak pressure and temperature , work output per kg of air andair-standard efficiency. Assume Cv =0.717 kJ/kg K and γ = 1.4 for air. [8+8]

8. (a) Draw the flow diagram of vapour compression refrigeration system and anlyzethe thermodynamic cycle applied for it?

(b) Explain the difference between the Bell Coleman and Joule cycel of refrigera-tion.

[8+8]

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1. (a) What are different forms of work energy? Explain each briefly.

(b) Why does free expansion have zero work transfer? [10+6]

2. (a) A domestic refrigerator is loaded with food and the door closed. During acertain period the machine consumes 1 KW-hour of energy and the internalenergy of the system drops by 5000 KJ. Find the net heat transfer for thesystem.

(b) 1.5 kg of liquid having a constant specific heat of 2.5 KJ/kg-k is stirred ina well insulated chamber causing the temperature to rise by 150C. Find ∆Eand W for the process. [8+8]

3. (a) What is perpetual motion machine of second kind? Why such a machinecannot be constructed in actual practice?

(b) Two Carnot heat engines operate so that the exhaust of one is the intake ofthe other; the highest and lowest temperature limits are 1200 K and 400 K.Determine the intermediate temperature if (i) both the engines give the samework output (ii) both the engines have the same thermal efficiency. [6+10]

4. (a) Explain separating colorimeter with neat sketch ? [7]

(b) 1 kg of steam at 8 bar, entropy 6.55 KJ / kg. K is heated reversibly at constantpressure until the temperature is 2000C. Calculate the heat supplied. [9]

5. (a) Derive an expression for heat transfer in a non-flow constant volume process.[7M]

(b) A spherical shaped of 14 M diameter contain ’H2’ at 330C and 1.3 bar. Findthe mass of ’H2’ in the balloon using real gas equation. [9]

6. An air tank of volume 9 m3 is at 68 kPa and 800C. Now water is injected into the

tank keeping the temperature at 700C. Determine the mass of water required toinjected so that the tank is just filled with saturated vapour. If the water injectioncontinues up to 25% more than what is required for saturated vapour calculate thetotal pressure in the tank. [16]

7. (a) Discuss the use of air standard cycle analysis for the study of internal com-bustion engines.

(b) An engine of 250 mm bore and 375 mm stroke works on Otto cycle. Theclearance volume is 0.00263m3. The initial pressure is limited to 25 bar, findthe following: (i) The air standard efficiency of the cycle. (ii) The meaneffective pressure for the cycle. [6+10]

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8. (a) Explain the working of air refrigeration system with a neat diagram?

(b) Derive an expression for the COP of Bell Coleman cycle. [8+8]

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II B.Tech II Semester Supplementary Examinations, April 2010BIO PROCESS ENGINEERING

(Bio-Technology)Time: 3 hours Max Marks: 80


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1. Discuss in detail about Chronological development of the fermentation industry.[4+12]

2. (a) Briefly explain about the material of construction for fermentor fabrication.

(b) Explain different types of agitators used in fermentors. [8+8]

3. Explain the factors to be considered for developing medium for animal cell culture.[16]

4. (a) Explain reactions involved that lead to loss of nutrient quality during sterili-sation.

(b) Describe methods of batch sterilisation. [8+8]

5. Estimate the theoretical growth and product yield coefficients for ethanol fermen-tation by S cerevisiae as described by the following reactionC6H12O6

−−−−−−−− → 2C2H5OH + 2CO2 [16]

6. Differentiate the heterotrophic and autotrophic metabolism emphasis on energetics.[16]

7. (a) Explain substrate limited growth and unbalanced growth

(b) Explain various phases involved in the batch culture. [8+8]

8. Enumerate the difference between the unstructured and structure models for mi-crobial growth. [16]

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1. What do you mean be fermentation and range of Fermentation process? [4+12]

2. (a) What is aseptic operation and containment? [4]

(b) Describe a typical aseptic, aerobic fermentation process. [4]

(c) What is sparger? Describe different spargers used in fermentors. [2+6]

3. Describe in detail the theory of oxygen requirement and supply in industrialfermentation. [16]

4. (a) What are the advantages of continuous sterilisation.

(b) What are the advantages of batch sterilisation. [8+8]

5. Explain the following:

(a) Elemental balances

(b) Available electron balances

(c) Maintenance coefficient. [6+5+5]

6. Differentiate the heterotrophic and autotrophic metabolism emphasis on energetics.[16]

7. (a) Enumerate the principle involved in the microbial growth taking an example.

(b) Differentiate between the growth in the batch and continuos systems. [8+8]

8. Describe how the microbial products can be classified along with the equations.[16]

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1. Mention about the Regulatory constraints of bioprocesses. [6+10]

2. In a fed batch culture operating with an intermittent addition of glucose solution,values of the following parameters are given at time t =2hours, when the system isat quasi steady state. Culture volume (V) = 1 litre Substrate concentration (S0) =100 gm glucose / litre Limiting rate constant (KS) = 0.1 gm glucose / litre Initialamount of biomass in the reactor (X t

0) = 30 gm Nutrient feed flow rate (F) = dv/dt

= 200 ml/hour Maximum specific growth rate = 0.3 h−1 Yield coefficient (YM

x/s) =

0.5 gm cells / gm glucoseDetermine:

(a) the initial culture of the medium (V0).

(b) Determine the concentration of the growth limiting substrate in the vessel atquasi steady state.

(c) Determine the concentration and total amount of biomass in the vessel at t=2 hour (at quasi steady state).

(d) If specific rate of product formation (qp) = 0.2 gm product/cells, P0= 0 deter-mine the concentration of the product in the vessel at t=2 hour. [4+4+4+4]

3. Sodium Bicarbonate is used as carbon source for the commercial production ofa micro algae. A constant cell density is always maintained in the reactor byharvesting the cells daily. The growth rate is measured regularly and an averagegrowth rate of 0.1 gm/lit (dry weight) is recorded daily. The total culture volumeis 1100 litres. Sodium bicarbonate is the only Carbon source and it is added daily.Assume that the cells are 50% Carbon by weight. Calculate the quantity of SodiumBicarbonate to be added daily if the conversion efficiency is assumed to be 90%.

[16]

4. What is meant by filter sterilization? Explain its application in media sterilization.[4+12]

5. Explain in detail the stoichiometry involved in the cell growth and product forma-tion. [16]

6. Enumerate the difference between

(a) Respiration and photosynthesis

(b) Hetrotrophic and autotrophic metabolism. [8+8]

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7. Explain specific growth rate with relevant equations. [16]

8. Describe growth and non-growth associated products formation with equations.[16]

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1. Mention about the Regulatory constraints of bioprocesses. [6+10]

2. What is meant by solid state fermentation? Explain the industrial application ofsolid state fermentation indicating the microorganisms, substrates and products.

[6+10]

3. What are the factors influencing the choice of nitrogen source? [16]

4. (a) Draw the schematic diagram of a typical continuous injector- flash cooler ster-iliser.

(b) Draw the flow diagram of continuous strilisation system employing spiral heatexchangers. [8+8]

5. Explain the concept of Degree of Reduction and its application in proton-electronbalance in biorector. [16]

6. Briefly discuss the following:

(a) Energy capture efficiency

(b) Oxygen consumption and heat evolution in aerobic cultures

(c) Heat generation and yield factor estimation. [5+5+6]

7. Briefly explain the following with respect to cell growth along with appropriateequations

(a) Substrate inhibition

(b) Product inhibition

(c) Toxic inhibition. [6+5+5]

8. Briefly discuss about the structured models for product formation and comparewith growth. [16]

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