I
2008

MECHANICAL ENGINEERING
Paper 1
3 /-lours 1 I Maximum Marks.' JOO
INSTRUCTIONS
Candidates shuuld attempt all the que8tions in Parts B C. However, thr.y have to choose only three questions in Part D.
Answers In ust be written in the medIUm opted (loe. English or Kannada!.
This paper has four parts:
A 20 marks
B 100 marks
c 90 marks
D 90 marks

lorlarhs allotted to each questlOfi are llIdicated in each part.

PART A


Answer each qu.estion in about 50 words. Each questwn carries 5 marks.
1. What do you understand by gyroscopic couple for its magnitude. Derive a formula 5
Sketch an intermittent motion mechanism and explain its practical application.
What is a chipless machining? Give examples. 5
Differentiate between relationship? production and productivity. Vhat is its

I 14/1
PAUTB
Answer each question ill about 100 words. Each question carries 10
Explain the principle of virtual work as applied to a system in equilibrium. 5
Ibl Using the principle of virtual work, determine the reaction of a beam AR of 8 m. The beam carries a point load 4 kN nt fl distance 3 m from A.
3.
Explain with sketch the different types of C8ms and followers. 10

4.
Explain the term whirling speed of a shaft. Prove that the whirling spced f(lT a rotating shaft is the same as the frequency of natural t1'an5'C1'Se vibration. 10

5.
fa) List the important factors that influence the magnitude of of safety.


Derive an expression for the impact stress induced due to a fallint: load.
6.
la) Draw Mohr's circle diagram for two dimensional state of Show stresses involved.

I Differentiate between hot working and working,

7.
What are advantages and dlsadvantt'lges of cast making tou] frames?



Draw neat sketch of a steady state rest usC'd in lathe'. n
8. I Explain the dIfference betweL'fl punching and blanking,
I l,j LIst the propertIes of materiill that influence spnng back. Explam why they do.
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9.
List ten principles of value analysis. 10

10.
Explain the working principle of explosive forming with neat sketch of schematic arrangement.

11.
What is acceptance sampling? 'Thy was it developed?


"What are the factors considered in designing a work station


I5I 14'1
PART C
Answer each question in about 150 words. Each question carries
15 marhs.


I Pour masses m mand mwhich ure 200 kg, 300 kg, 240 kg and
s4 269 kg respectively rotate in a plane. The corresponding radii of rotilLion arc 0·2 m 0·]5 tn, (J·25 In and 0·3 ill respectively and angle betwf'en successive masses arc 75° and 135°, Find the position and magnitude of balance mass required, if its radius of rotation is 0·2 m.
I:J. A machine part of mass kg vibrates in 8. ViSC01lS medium. DetcrmilW the damping coeHicient when a harmonic exciting furcp of 25 N in a resonant amplitude of 12·5 rum with a period of 0·2 seconds. If sy:..;tl'l1l is excited by a harmonic force of frequency Hf., what will be percentage increase· in the amplitude of vibration when damper L"l removed as comparpd with that of with damping?
14. An f'1S rod em diamctfll' And 2·2 m long is subjected to n gradurt1Jy lllcreasing COIlll-'reSSlon load. the buckling luad. Find also the maximum lateral ddlection corresponding to the buckling load. Both ends df the rod are pinned.
2
TakeE 101 kN/cm2 <ll1d yield stress kN/cm.
15.
Explain how the ED!J process is capable of producing complex shapes. What is the difL.:nmee bct\'een photochemical blanking and cbemil:<tl Jd:mking If)

16.
a compnny manufacturing elce-tronic calculators produced J 0,000 Ly employing 50 people at 8 hours/day for 25 WI wi is the producLion t1nd producti'ity The company increased Its; production to 12,000 calculator:: by hiring 10 F.ldditionaJ (it hours/day f{lr 2:j da,vE>. Vhat is the production and productivity

17.
Vhat ii:J the ABC anaJy:sis of an invi2ntor.' control'? ExplaH;.


[Turn OV€,r
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PARTD
•

Answer any three of the following questions, each in about 300 words.
Each question carries 30 marks.
IR. Design rubber belt to drive a dynamo generat.or 20 kW at 2250 r.p.m. and with a pulley 200 mm diameter. Assume dynamo efficiency to be allowable stress for belt is 2·1 MPa, density of the rubber IS 1000 kg/m3, angle of contact for dynamo pulley is 165°, coefficient of friction between belt and pulley is 0-3. 30
19. A central steel rod 18 mm diameter passes through a copper tube 24 mm inside dlameter and 40 rom outside diameter. Steel rod provides with nut and washer at each end and they are tightened on either side of the copper tube until a stress of 10 MPa is set up in the steel rod. The vhole assembly is then placed on lathe and turned along half the length of the copper tube removing to a depth of 1·5 rum. Calculate the stress nnw existing in the steel rod. Take E gteel 2 Ecoppcr" 30
en
m
20. A porter governor has equal arms each 250 rom long and pivots on thE'» axis of rotation. Each ball has a mass of 5 kg and the mass of central r-load on the sleeve is 25 kg. The radius of rotation of the balt IS 150 mm
whlln the governor begins to lift and 200 mm the governor is t maximum speed. -r""lind the minimum and maximum speed and rangL' of speed of the governor. SO
21.
Vv11llt types of chips would be produced during machining of materials and machining cast iron Explain. are tOll1 temperatures low at low cutting speeds and high at higher cutting speeds

22.
What are the technological based productivity improvement techniques?




Explain, .it.'
I1412 I
2008

MECHANICAL ENGINEERING
Paper 2

Time: 3 Hours J Maximum Marks: 300
INSTRUCTIONS
Candidates should attempt all the questions in Parts B However, they have to choose only three questions in Part D. C.
Answers must Kannada), be written in the medium opted (i.e. English or
This paper has four parts:
A B C D 20 marks 100 marks 90 marks 90 marks Marks allotted to each question are indicated in each part.


14/2

PART A 4x5=20
Answer each question in about 50 words. Each question carries 5 marks.
1. State Zeroth and First law of Thermodynamics. 5

Differentiate between static and dynamic pressure.


Explain different modes of heat transfer. Write one dimensional equation for each mode. 5


Cd) Explain two types of air standard cycles used In Ie engine. 5
14/2
PART B lOx 10= 100
Answer each question in about 100 words. Each question carries 10 marks.
2.
Define the terms internal energy and enthalpy. Differentiate between an engine, a refrigerator and a heat pump. 10

3.
Differentiate between steady and unsteady flow, uniform and non-uniform flow, laminar and turbulent flow and compressible and incompressible flow. 10

4.
One meter long nichrome wire of resistance 1 IlQm is to dissipate power of 10 kW in the surrounding fluid which is at 800 C. Find the diameter of the wire if the maximum operating temperature of the wire is 100e C. 10

5.
With sketch explain the lubricating system used in an Ie engine. 10

6.
With schematic diagram explain the working of a vapour compression refrigeration system. 10

7.
Explain the binary system of power plant used in nuclear power plant. 10

8.
Differentiate between parallel, counter and cross flow heat exchangers. 10


B. Sketch and explain the working of a locomotive boiler. 10
10. Water vapour of 5 grams per kg of atmosphere air is removed and the temperature of air after removing the water vapour becomes 250 C DBT. Find Relative humidity Dew point temperature. Assume condition of atmospheric air is 350 C and 60% RH at pressure of 1·03 bar. From psychrometric chart for air at 350 C DBT and 60% RH,
Pvapour' Pv 0·05723. 10
11. Draw a neat sketch of centrifugal pump and explain its parts. 10
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PARTe 6x15=90
Answer each question in about 150 words. Each question carries
15 marks.

12.
A vessel of 0·4 rn3 capacity contains 2 kg of wet steam at 6 bar pressure. Calculate the volume and mass of water and volume and mass of dry steam. From steam table, specific volume of water, vf= 0·0011 and saturated steam, vs 0·3155. 15

13.
At a suddenly enlarged water main from 240 mm to 480 mm diameter pIpe, the hydraulic gradient rises by 10 mm. Estimate the rate of flow. 15

14.
Aluminium fins of rectangular profile are attached on C plane wall with 5 mm spacing. The fins have thickness, Y 1 mm, length, I 10 ill and the thermal conductivity, k 200 W/m K. The wall is maintained at a temperature of 2000 C and the fins dissipate heat by convection into the ambient air at 400 with heat transfer coefficient h 50 W/m2 K. Determine the heat losses. 15

15.
Draw a neat sketch of a simple carburettor and explain how it works. 15

16.
An oil of specific gravity 0'88 and viscosity 3·8 poise flows in a 5 cm diameter pipe at a rate of 4 litres/sec, Comment whether the flow is laminar or turbulent. 15

17.
Sketch and explain a summer aIr conditioning plant layout identifying each component. 15


15) 14/2
PARTD 3x30=90
Answer any three of the following questions, each m about 300 11.Jords. Each question carries 30 marks.
IH. A non-uniform part of a pipeline 5 ill long is laid at a slope of 2 in 5. Two pressure gauges each fitted at upper and lower ends read 20 N/cm2 and 12-5 N/cm2. If the diameter at upper and lower end are 15 em and 10 em respectively, determine the quantity of water flowing per second. 30
10. The compression ratio of an air standard Otto cycle is 8. At the beginning of compression process the pressure is 1·0 bar and temperature is 300 K. The heat transfer to the air per cycle is 1900 kJlkg of air. Calculate
the pressure and temperature at the end of each process of the cycle
Oi) thermal efficiency
the mean effective pressure 30
20. A three stage compressor is used to compress H2 from 1·04 bar to 35 bar. 25
The compression in all stages follows C. The temperature of air at the inlet of compressor is 288 K. Neglecting the clearance and
assuming perfect inter cooling, find out the indicated power required in kW to deliver 14 m 3 of H2 per minute measured at inlet condition and also determine intermittent pressures. Take R 4·125 kJlkg K. 30
21.
How are water turbines classified? A Pelton turbine has a bucket speed of 12 m/sec and is supplied with water at the rate of 750 litreslsec under a head of 35 m. If the bucket deflects the jet through an angle of 160°, find the power. The coefficient of velocity is 0-98. 30

22.
What is the necessity for using solar energy With neat sketch explain the working of a power plant using solar energy as power source. 30