ies mechanical engineering paper 1 2006

7/27/2019 IES Mechanical Engineering Paper 1 2006

http://slidepdf.com/reader/full/ies-mechanical-engineering-paper-1-2006 1/14

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I.E.S-{ORJ) 2001\ I ol 14

MECHANICAL ENGINEERING J~ - = = : : = = !

I.

2,

3.

PAPER-I

I f N,1 IS the specific speed or a pumphandling larger discharges at low headsand N,2 is tha t or a pump hand ling low

<.hscharges nt h1gh heads, then "luch oneof the follo\\ mg IS correct.,

11. N'f1 >N.z

b. N01 < N,,

c. N,1= N.l'

d All the above three are p()Ssible underdifferent situations

Consider the following ~ t e m e n L S inrespect or impulse steam turbines

I Blade passages are of constant cross·

sectional area.

2. Partial admission of steam ispermissible.

3. Axoal thrust is only due to cbru1ge in

now 'e locil) of steam at mlet andoutlet ormoving blade.

Which of the statements given above are

correct?

a. 1. 2and3

b. Only I and 2

c. Onl)' 2 and 3

d. Only 1 and 3

Consider the fo llo\\mg stntemcms

I. Fo rward swept blade impeller is used

in draft fans.

2, Fonvard swept blade tmpeller is used

in room air- conditioners.

3. Radial lipped blade impeller is used in

drun fans.

4. Fom•ard swept blade impeller is used

in exhaust fans

Wl'uch of the t a t e m c ~ n gn·en above is/arecorrect 'I

a. Only I

b. Only 2 and 3

c. Only4

d 1 2,3and4

-1.

5.

,,

7

tn an a.xial llow im pulse turbine. energytransfer takes. place due to

a. Change in relative.kinetic energy

b. Change iJ> absolute kinetic energy

c. Change in pressure eoerg)•

d Charlge iu energy because orcentri fugal fo rce

Constder the followmg

I, Superheater

2. Econon>izer

3. Aor pre-heater

4. Condenser

Whtch of the abcve tmproYe o\ erall steam

po\ \ cr plant emciency'l

a. O 2and 3

b Only 2 and 3

c, Only I and 4

d. I, 2. 3 and ..t

Cons•der the followmg.

I e c t o r2. Economizer

3 Bioi\ -off cock

4. Steam stop vah·e

Whtcb of the abore 1s/are no t boilerlU0 UJ1lU1gs ?

a. Only I

b. Only I and 2

c, I , 2 and J

d. 2 and 4

In a steam o r to mcrease the Yelocity

of steam above sontc velocity bye.xpunding s team below critical pressure

a. A vacuum pump is added

b. Rmg diffusers are used

c. DIYergen t portion of noule is

necessary

d. Abrupt change in cross-section is

needed



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9,

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Jl .

12

Wilson line io s o c i a wi Uo which ono

of the: follow in& I

a. Totol steam con.•umption with r""pectto power output:

b. Supen;onic flow o steom (hrough

noz7Je

Nozzle Oow l'' ith tiiction

11 Sop <m<atuo':lred Jlnw nf sremn thmug)o ,

uWhich one of the ti>llowing expre<>es the

ma.d mtun e f t i c i e of a Par<turbin e ?

'2co•' a•• 1• cosl! a

coslab.

1- 2c<>S ' a

cosac.

d.cos i(

2

where a is th.o ,iet angle at the entrance.

When is the greate:;t econom y ohta ined io

:o '"genera tive feed heating ?

a. Steam. IS extracted from only onesuitable poim of a steam turbine

b Steam is oxtroeted only fTtJm the las!

Stage Of II <team turbinec. is e_«tractcd OnlY from the first

Wlllf!t of Asteam turbine

d. S a m ;. ex trac ted from $Wera t placesin dilf«cnt slog<>s of t c : ; ~ m turbines

lu a rcac!ion turbine tlte enthalpy dl 'O J> in a

st>g11 U. 60 units . 'Ibe enthalpy drop iu thomoving bbdes is 32 vnil3 .

Wloat is the degree of rca.:tion ?

"· 0.533

b. 0.284

c. 0.461)

,1, 1.875

Which of the following C.'lll be the

c a l l . " e l c a ~ or rm air-cooled m pgetting ~ dUl·ing C/pttauon 11. Insufficient lubricatinj! oU.

2. Bro ken valve s trip.

3. Clugsed iutnkc liltcr.

13.

I"'

15.

16.

17.

Seleet the con-eel answer using the code

given beiC>W :

a, Only 3

b. Only 1 and 2

c. Only 2 and 3

d. l. 2 and 3

In a cenirift•gal compressor. how can thel>t\;S.sun: r:ttio be increased ?

a. Only b) incre:osing Ue tip speed

h. Only b) decreasing tloe mte1tcmpcrulllrc

c.. B)' b<Jtl• • · and h.

d. Only hy increasing the inlete m p t u r e

The power required to drive n hubo-

compressor fur ;a giveu pressua" ratio

wht:u

l l, A.ir is heAled at <:o lry

b. Air ls cooled a1entry

c. Air L cooled al exit

d. Air is healed a l <lXil

Il l an •xioi now CO I'CI)trt:S80r. WU<::tl lhct

degree of reaction is so• .. l implie8 lhnt

"· Work dono in m p will be theleo.•I

b. 50% J tnges of the compressor will be

ine.llOCHve

c.. Pressure nftar compress ion will be

optimum

tl. The comt1ressor will h:•vo M)'lnme1ric;tl

h l ~ < l ·

In Cllsc of hqm cl$. what ,;; the hinorydift'u siOii "')ctl1cit nt proportional to'/

a. Pressure only

b. I'c.mperature

c. Volwno oJily

d. All the ah•lVe

A copper block and an oir mass hlockhaving similar dim ensions a r¢ subj ect,..! lb

m m heallransfC:r from one fJce of

eodo hlock. The other face of the blockwill he reaching to Ute same tem pernture at

a rate

a. F""tet in air block

b. F""rar in copper block

c. Equnl ln uir •• wo U3ii copper hlook



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20.

21.

22

23.

d. Cannot be predicted with tho s1veninfonnntion

l'he equation of etl'ec.tivenes.•

E 1 - ~ ' I V fat ahea t . : : < c h . . , n g ~ . - r is valid

in ihec.;Heof

a. Boiler and condc"scr for p•nllol flow

b. Boil<lf •nd condenser for c o u n t ~ r f l o wc. Boiler :md condtmser lilv hmh par•llcl

Oow and onunterllo"

d. Gas tut·bioe for both pa•·•Uel !low andcountcrllow

Tb"mtal diffusivityo[a u b s t a n ~ is

u. lnve,.,dy proportional to thennalcQntt\lctivity

b. Dir""lll' proportion•! 1<1 lherm:tloonductivity

.:.. Olte\ltl)' pmporllooal to the S<jUat" of

l.hcnnal conductivity

d. Jnver•ely proportion> I lt1 the squ•" ' ofthermal condU<:tivity

Air cun be be-l ll<!nled by •W.m in • bc.tt

exchanger of

". Plate type

b. Double pip <: IYP" witl1 £ius on sloamside

o), Double pipe typo wi th fiM on sltsido

d. Shtlland tube lyp<:

A IT1 ttal plate a s u r t ~ c e are.• ol' '2m' .tltjclme.s!l lO mm and a thotmnlconductivity of 201) W mk. \Vbol is tho

lho:rmal rcsi$t.nnceofthe plate ?

4 1 .K/\V

b. 2,5

c. I.S

d. 2S

10 ' KtW

10 'K 'W

10·5 KI\V

W b . i ~ b 0110 of Lhe foUow iug l;):<pt·os>es 01etherm;al diffusivity ofa subst.an.::c in Lcrms

of thermal conctu'cth·ity (lo. mass density(p ) and specific heal (c) 1

a. k2pc

b. 1pkc

c. k/pc

d. pcik'

Wbat is lhc rntio <tflh"l'lllal conduotivity 10ei<>Ctrienl conduclivily equal to 'I

n. P l - : ~ n d l l number

24.

25.

26.

ut IJ

b. Sclunldt number

c. Lorenz number

d. L""'•C. number

Motch List - I with l.ilit -II and sdect 01e

correct nns11 er using tbe code given belowtbe L i s t ~L ist •1

A Radiation he.•L U-alli!fer

B. ConduGlion heal transfer

C. Forced oo n<·ection

D. Transient heat llo11

List · U

1. Biots number

7.. Y cw lilctor

Fourier's l>w

4. Sl.1nlon number

••

A

4

0

3

c2

D

b. 2 4 J

c. 4 2

d. 2 3 4 l

l\f:olch List - 1 witb List • n and select the

con-eel ons"er using the code given belowthe

List • I ( P h ~ n o m c n o n )A. Transient conduction

B. Ful'ced con,·ection

C. Mass truMfet•

D. Na tural convectioo

List - U (Assodairo l ) i m e n s i o n i i i S ~P j l r a m ~ t e r )I. Reynolds numher

'2. Grashoff numher

3. Bioi numher

4. !Vucb numbeo·

5. Sbt:rwood nut11ber

"·d.

3

5

3

5

fl

2

1

l

1

c5

s

4

f)

2

2

Whicb on« of Joo following is Uoe e<ttt-ect

siMeuHml '1



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18.

2'.1.

30.

A nuc lear fiSsion is i ~ i t i a t c d when thu

criticul energy us C<llllpllrcd to neutmnhindin!). <nergy ntoms is

a. less

b. s a m ~c. more

d. cxnctl) tWu Lmes

What is the Oash po int ora li4uid fuel ?

a. fltc tcmpcrumrc ut which the fuelignites sponttmcously with a bang

b fl1 te.mpernture nt whrch the fue l

e m i L ~ vapou rs at rate '"hich r o d t • ~ e ~un inllammahlc mi:<"turc with air

c. The lijntperuturc at which the fuij lignites wi th a clearly VISible Oush

d. The temperntlir•· at which the fi1cl

ignites wi thout a spad'

What IS t.he function 0 I' hcuvy water 111 unuclear reactor?

a. It e r v ~ s us u :onlan t

b It serves as a moderator

<:, II serves as a coolant ns well as amodeml\>r

d It Krvcs us a neutron absorber

Consider the loii<)Wing stmcmcnrs :

The ~ a s c ~ measured dirccLJy h) OrsutliPIIRriltus front n Oue gas stunp tc urc

co1. 0)1u1d N1.2. !3omb ca lorimeter m e u s hlgher

caluritic value , r fud m constantp r ~ s s u

3. For burning I kg of fuel (carbon) 10

curl>on monox1de. the stoichiometricquantityofair required is 8/3 kg.

Whichof the st1lll'111tnts given nbuw is/arc

c o r r ~ c 'I

a Ullly I

bOnly 2

c. Only 3

d LlandJ

In vapo ur C f > l p r e s ~ I O f l refngcrntioncycle for makm g tcc. the condensing

tcmpcratlli'C" tor h1gher COP

a. Should be n c ~ r the critical tcmperlllltrcof he rcfrigcmnt

b Sht>uld be utxwc the cnticultemp11ruiure of he refrigentnt

31.

32 .

33 .

34.

t uf l l<:. Should be much below the critical

temp<.,nuurc l'l!frigcram

d. Could be of any vnl ue liS it docs notofli:ct the COP

. s

fhe t1gure !liven above depiCs saturationdome fur w.mer on the tcmpermure-entropyplane. Whut temperature difference.1T shown on n typical ISobar line known

as•

a. D c g r c ~ <Ifwet bulb d c p r c S ~b. Degree o 'saturauon

Degreeof u b ~ o od_ Dcgrc.c ()f rcltcat

Whnl does application ur centrifugal urr

co mpressors lead to?

a. L11rgc fron tul urc(l ofuircruft

b. Higher now rdle 1hrough the engine

c. Higher ai rcrnfi spec<l

d. Lowe r frontal urea of he llllcraft

Con>idcr

the following

st:ttemen

t£

indi0111ing a compariso n w c e n r < l CandJet pro pulsion ~ y s l c n t s :

L !3oth rocket :md jet engines corry thefuel nnd os.idllll l

2. Rockel' do 11\lt emp loy compressor orpropel!or.

J. R<>ckets can orerntc 111 vncuum also .

4. R u c k ~ t s can use solid rue ls and

oxidantS .

Wltich of the statements given above nrc

correc.t'l:t I, 1.. H nd 4

h. Only I nnd 2

c. Only 2. 3

d Only 1. J ao<l 4

Whar· 1s the pnrpose or employ ing

supercharging for nn engine

a. To provide forced CO<IIiltg ttir

b. To mise exhaust prc.ssurc



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37.

311.

To inject e x e c ruel for coping wiUt

high.:r

d To supply a.n ontake of air at a dens itygreater than the dens ity of the

!Surrounding

Coru ider the following statements ·

I . Superehnrging s . : s the p ower

I. •outpU! o ao engmc.

2. h t ~ r g increases the h r : atltt:tm>l cfficit:ney considera:bly.

3. Supereharsirlll help• scavcngin!l oJcylinder$.

Which of the s tatement> given abov" arecorr..:ct ']

:c Only l and 2

b. Only 2

c. ( lnly I >net 3

d. L hnd 3

'Where does rnixing of litel •ud alr luke

plnce in case of d iesel engine 'I

"· wjccliocJ pump

b. lnjoetor

ll . Engine eylfnder

d. lnleLJnani fold.

C'ons i4er the tb llowiog Rntements :

1. ln the Sl tau!.ines detonation occurs

ne:J1' U1e end of combustion whereas in

Cl ~ knocking 0\..'CUIS near thei u n i n g of r u b u s t i

2. In Sl engines no problems are<;ncountcred on account of pre-igniliotL

3. 1.ow inlet prtmurc and t c r u p < ~ l Uruduc" kneeling tcnd tn ey in Sl

engines bnt increa•e the knockin gt e n ~ n in ("I m gines.

Whicb of the st:ctemeni• gJVen ahow >re

C\)ITClCI 1

a, I, 2 and Jb. Only I and 2

c. Only 2 and 3

d. Only I 011d 3

The tendcnc) Ill'petro l to d i:IOMte in termsof octnnc number is d<.etcrmin()d by

comparison of fuel with which uf the

fo llowing1

l.so-oct:me

39.

-10.

42.

S ut

b. !'vru.:tuno of nonnol heptane :md ls<>-

oetane

c. Alpha methyl naphthalene

d. Mixture of molhnnc and cllmnc

For tltc srune indicated work per eyclc.

mean speed and permissible t \ J ~ t i of

speed. what is the size or ny,,hcel

required for o mulli-cylin(ler cn11 inc incomparison to a single-cylinder cngind']

a. Bigget•

I>. Smnller

c. Sam e

<1. Depends on n n n l dliciencJ nf the

engine

C o the following swtcments:

I. For n Oioso l cycle. ll1u thermal

etticieooy decrenses"" the cut ut'fratin

2. In a petrol engine til e high voltage for

spark is in U1e o1der of I000 V

3. The mote-i• l l'or cent re electrode inspark plug is COJ'h OIL

Whic)l of tl>t t a t e t n e n ~ £!iven ah<\ t is larecnrrtc.t ?

a. Only I

b. Only I and 2

c. Only 2 and 3

d. l, 2 and 3

Con• lder lite folio\\ ing :

\ ·ulumetJic e fficiency of a recip!1loat.ingair compn.ssor iucn::tsQs with

L increa•c in clenronce rJt.io

2 decre.1sc in i w r y pre.snre

3. multiytaging

Which ofthe st.:ttemcnts given above isi:U'\!

correal V

a. Only I :md2

b. Only 2 and 3

c. Only 3

d. I. 2 and 3Whnt is the prel'etTcd int<>reoo ler pl'cSsorelilr a two Stage air comprcgsur workinghelwet:n the suction e - ~ . s and U1e

prtssu.re pa?

a, (p, 1 p.1)12

b. (p4- p,)l2



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44.

.15.

46.

c. (p,

" · (p. • rJl'',Consider Ihe lollowing stn temems :

In order lo prcvcul detonation in n spark

tgpition engine, U1c churge away lton1

spark plug should have

I, ' " "' temp<'rtllurcl . low dcosit)•

3. long ign icion delay

Which of the swtemems given above is/are

co rrec t ?

s. Only I

b. Only 1

~ Only 3

d. I. 2 and 3

--=G=L:.........-/

The energy grude line (f.GL) to r steady

now in a unifonn diameter pipe is shownabove.

Whicb of the l'ullll\\ lng items is contttioed

in the b;lx ?

a, A pumpb. A tlU'bin<

c. A pnrtinlly closed valve

rl , An nhn1p l expansion

A compou11d pipeline c o n ~ i s t s of lwn

pidces of idemi cal The e t t u i v : ~length of same d i a m ~ t c r and same frictitmfactor. for the compound pipel ine is L.1

whe,n pipt."s ore connccLcd in r i c . . • and is

L, when conn ected in parnllcl. Wh al is !he

rutio of equivnlenl lengths Loll :?

a. 32 : I

h. 8 : I

c. 2 : J

d. ../1 : J

For irrota1ioual and incompn:ssiblc now.

U1e velotity polemiul und su-e:m1 !unction

are given by <II and II· respectively.

Which on< of he fo llowing sets is c o ~ c l ' )a 'J

1•r = 0. V2•t•: 0

<17.

49.

50 .

b. V'1p '" 0. Vw = 0

c. V2<P = o. v " ' u' 0 ' 0. V'IP ~ • V·•v

h of I I

In o two-dimcnsinnal c o m \ ~ l b l csteady now , the velocity component u =Ae' ()btaineu. What is the order

componen t" of ve locity 1.'

u. v ::

b. v = A ~c. v = -Ae'y + ltxt

d. v = - Acl> ;- lb·)

For n c;;lcudy twt1 .dbnc:msic•nul o w tbc

sCttlnr componencs ofthe ve locity lield areV, = - 2x: V, = 2y, V. = 0. Whut ure the

0 m r o n ~ n i S of acceleration ?

o. a,. = 0, n, = 0

b. u, = 4x. a, =0

c. u, = 0. u, "' 4y

d. a, = 4x, u, =4y

Consider U1e follo>Ving statements

regarding a pa!h iu lluid Jlow:

I. A puth line is a lim: truceu by a single

particle over n time inlcn•aL

1. A path line shows the p o s i t i o n ~ o f ~ 'm pat1idc:. at successive time

m L3. A pmb line sho\\s the iusmnumcous

pos itions of a number of particles.passlng r u u g h a common point atsome previous time insiJJms.

Which of the stolcmcnls given nhovc nrc

correct?

a. On ly I aJ>d 3

b. On ly I and 2

c. OnI)• 2 am! 3

d. I. 2 and 3

A l>eakcr of water is fa lling l'r\.>e ly u•1dcr

the influence of gruvlty. Point Fl is on thesurlilce and poiLll {' l-; \'cnically below Bnear bottom o f ~ ~ ~ beaker. If P is

prcssurc at pilint B and P tl1c prcssul'l! atpoint C.then "hich nne nflhc fi• ll•)wing is:COrT"CCl 'l

~ Pn = P1

b. Po < Pr

c. "" > 1



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d. Insufficient int0nn.1t ion to cl<ltenninoany of the: above

51. A homogeneous solid of any arbitraryshape flools upngbt in a homogeneousliquid with inunen;cd volume \ and is in

stuble O<Juilib•·ium . If Otc solid isMe rllJmed and made to Jloot upstde down

in a difl'crent h1lmOgcneous liquid with<*actly MOiftt vuhuno V >hovo Inc liquidsurface_ lbcn lhe cc tuiJihrium

a. Would be stab le

b. Wou ld be neutral

c. Wou ld bc: unstable

d 1\tay or •n•y nor be •tnble

52 A 25 em long prlsmotic homogcneQussolid in water wid1 its ~ x i s verticnland JO em projecting above water s urface.

1f th" snmu soJjd floats in son1c oil wiUlOXJS vcrticnl Jnd 5 em projecting above theliquid surface, what ;, lhe spedflc grnvily

Qf thc oU ?

• • (),6()

b. 0.70

<;.. 0.75

d. 0.80

53. A semi-cin:ular plane area of diam<leJ' 1

m. rubjcctcd to a uniform gas pressure

of 420 kN/m!. \Vha l JS the moment ofU ~ r u s t

tapproximately) on the area "bout: U g h ~ d g e 1

54.

55 .

11. 55 kNm

b. 41 kNm

c. 55 kNm

d. 82kNm

A hori:z.onbll oil tnnk ;, in lhe of •cylinder w ~ hemispherical end•. If il isexactly half full. what i• the ral!o of

mngnitudc Cof lhc vertical C<Jmpon.'Tll il f

rcsulto.nl hydrostati" tllfUSt on on"

htflliBJlhoricnl end t.o, U1a1o f tl1c hmizonL1I

com ponen t'/

" · '2Jn

b. n/2

4/ (371)

d 3nt4

Tite A;tnnd !lrtl nluto"phoric prosl$UfC 762

r»m of llg. At a specific loc,11ion, lhe

IJ•J<Qmctcr read, 7tHI mli1 of Hg. A• t h i ~

7 ol 14

piAco;, wha t does an 3bsolut" pJ'I:ssuro of380 mm ufHg correspond to 'I

-a, 320 mm of Hg vne-aum

b. 382 ofHg vacuum

c. 62 rom of l lg vnouum

d. 62 mm uf !!•ugc

56.A manometer is n1ade of a tube of uni fom1boJ'<l uf 0.5 cmz CJOss-sectionnl areas. with

on< limb v<-or·icol nnd UJo other limbin.clined >I 30° lo the ho ri:z.onto l, Bolli nf

ils limbs are open to ;•lmosphere and,initially. it is partl.v filled with 4

manometer liquid of •r ccilic w·•vity 1.25.If lhen nn >ddilional ,.,,hlme or7.S em" or"" ' er i• pc1ured in lite inclined tuhc. whall1 Ot t •·ise of tl1o mon illc.u6 in lbc vcrtiClll

luhe?

a. 4cni

b. 75cm

c. 12 t111

d. lh'm

57. A vert ical clean glass tuba of unifom1 boreis- a pie7..ometer to measnre the

pressure o( liquid at> po in l The liquid bas

• specific weight of 15 kN/m3 aud •

r f ~ c c len.>1on of 0.06 N/m in coniMI11ilh ait. It lor lh c: licWid. the JlngJe ofw11L'cl g11$s i• £cro 3nil capillarycisc in Uu: tube is not to 1::-;cccd 2 mnL

whnl is the required minimum diome!Of' of

the tu be: 'I

S8.

59.

a, 6 11111'1

b. gmm

c. 10 m1rt

d. 12mm

When the JlresstJJ-e on 11 given mass ofliquid is ~ ~ ~ > t « < from 3.0 I\1Po to 3.5

MPa. the density of the l i ~ i d incre.ucsfTom 500 kg'm' to 50 I kg/m . What is Ihe

avernge va lue of bulk modulus of (h. ,liqujd over tJu.t given pressure runge '1a. 700 lvfi' n

b. 6(K) M P ~c. 500 tv!Pn

d. 250MPo.

A.-slll'lion (A) : Nozzle control guvcrnin.gcnnnol ba tn reaction ste.am turbines.

R c 3 ~ 0 n (R ) : fn l'u;&c.liou t e a m h ~ r brul l iorlmi•s icm nt'srenm must lake place.



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60.

61.

62.

63.

'' · Both A and Rare individU4lly !nrc 1mdR is theC()rrect : q > l • n ~ t i o n ofA.

h. Both .\ ond Rare individually tme butR is not the correct explonalion ofA.

c A is true but R i< f a l ~ ed. /\ is fR l§c but R is true

Assertion (A) c Fire tubo u i l o ~ de.• 11111

opomre at high J)fC!iSUrel< whjle water inhc

hoi\ers ''l,eratc: at high pressures,

Rea.on !l'l.J Oue to high temperatuN of

llu.e ga<cs. fire tubet; m a fail due to creep.

a. Both A and R "re individually lme and

R is C<Jrr'ect explanatjon ofA.

1>. Both , \ and R ar e lndividuallv true but

R is not the ~ o r r e c t e . ~ p l a n a t i ~ n of A.

,-\ is tme bul R f•l'e

tl A is fn loe hut R is true

A . r1Jon (Al : 'r be internal en.,gy

depends on U1e internal stare o.r a body. •s

dt>temtined by its tempmwre. p r e s s u ~compo.!t ilion.

Re:oson (R) : lntduJal ~ n c r g of a suhstanc«

docs not include nuy energy i t may

posse-ss 3 result of its mo.1croscopic

position or movement.

n. Bolh A and Rare individ11.1lly true nndR is tl1c correct v l • n ~ t i o n ofA.

h. Both .-\ 3nil R :<re j0dividunll)' true hut

R not tl•c correc t r t • n • t i o t > ofA.

c. A is true bul R ls false

d. A is false butR is true

A . rtion (AI ; ·noc change in nvnil:rl;rility

nf a •ystem is equ•l ro the ch:ange in !heGibbs tlmction or system at constanttemperature and r e s s oRcallQn (R) . Tbc Gihhs 1\Jnotion i• •l•¢fulwhen cvaluntjng. Utu avuibbility of syes-lcul)j

in wbich chemical reactions occur.

11. BoUr .\and Rare individt1.11ly truo 11ndR is the correct e:q>lonution ofA.

b. Both A and Rare individlllllly ln..: hu tR is not the correct explnnation ofA.

c, A is md but R is false

d. A l. fabebut R i• true

As$cr1iO n (A) . All t:()nslanl ctllfll(l)'

processes are adiabatic, but oil odiabuticprocesses are- not isentrop ic .

64 .

6S.

66.

61,

8 of

Reason (R) : 1\n ndial>atic process whi.>h

resists the exchonge of energy to thesurround ings Tnll)' hAVe irrevt:rsibillty dUe

to friction ond b c t ~ t c!Onduciion.

lL Both A and R Jrc individunUy lmd and

R the C(11"l'l;;ol explanation of t\ .

b. Bolh A und Ran; Iudividuall) ! I ' l l ~ but

R is not tho correct crplnnnlion ofA.

c. A i> true but R m rise

d. A is folst but R ;. true

.-\sscnion (AI : At "CI) higJT densities,

<!llntprt:llsihilh y ut' a teal gas is le.s thanom:,

Rc:oson (RJ : As k'tllperntw·c i>;

consjdemhly reduced, tho molecules >re

brought "loser togetlrer and t11ermqnuclearattractive forces b ~ c o m e greak.'1' atpNSSurcs aroLWd 1\U>a.

• · B o ~ • A and Rare individuaUy ll'llt: and

RU. the cor:n:ut c:< plruwtion of A.

b. BoUt i \ •od R •re 1ndividWllly t r u ~ but

R is not the coLY«·' ~ ~ p l n n n t i o n of :\.c. A i> true but R is false

d. A is false hul R is true

Which one of the following is used to

bring down the speed of on impulse s1<'111ll

turbine to pnactica l limil-; •1•· A cc'TltTifitg• lgownuJr

b. Co•n1>ounding nf U1c turbine

c A large Oywheel

d. .\ senr box

C o n t i d e r rhc IOllowing fiw :1 t c : . : . 1 1 ~ tlll1hine

pnwer pllmt:

I. Reduction in blade erosion.

2. lncrcasiJ ln turbine speed.

3. lncr.:asc iu specific ou tput.

4. L ~ e in cycle dlicocney .

Which orl1e ahove occur/occur.o due torehcntingvf C o 1 m '

a. Only I

b, I and 2

c. I. 3 und 4

d. 2 -uud 3

C u s i d ~ r 0•• lollowing featu res fur· a g•rs

b i n ~ > plnnl :

1. 1111-.'tCOO!i.ng

2. R c : g ~ 1 1 e r a



w w

w . e x a

m r a c e

. c o m

8,

6'9.

70.

3. Roheot

Which of the abow fcJtutts in n

go$ turb ine cycle increase the work ratio'/

"· 1, 2 and 3

b. Only l •nd 2

c. Only 2 an<l

d. Only t and 3Which of ll1e fo llowing parameters

decre.'ISe across 3 no1mal shockwave ''

I. Mach number

2. Stat ic tlfessl\fe

3. S t.:l.g.nation prc..s.surc

4. Static tempecalUI'C

Select the Currc:ct a n ~ W c r 11.'>-ing thd o d e ~givcu be low :

a.. Only I >nd :>

b Unly 2 and 4c. I. 2

d. 2, 3 nn\1

Wllt11 •ro shock wovos formed iu air

compn:ssol"'1

a. Moth nurubur < 0.9

b. J\iacb number . 0.9

c. t . ach numher = 2

d. Msch numl>er changes suddenly ii·om

one·va lue tu :mother

Which nf the followinl! s tatemen ts arecon-<:<:1 for mult.i.stagiug in a rc:ciproculingnir comprussol' ')

J. lt decreases the vo lumetric:. c:flkicrtC")'.

2. The 1\urk done can be J't;<l\Jccd.

3. A hi&h·pressure cylinder is

o qu ircd.

4·. ·n,esize of flywheel is reduc<ld.

:;elect the correct answer II.Sing the codesgiven belou :

L land 3

1> . 2. ;\ ond .I

c. 1, 3 a n d ~d. I. .Lind .I

Whal is the rntio or the iSL'f\lrOI)IC \I'OIk toEuler's work lulown as ?

P r e s s u ~ co.::ffid1011l

b :;tip ractoo'

c. \Vc>rk foetor

72.

73.

74.

75.

., "' 14d. Degree ofre3etion

Consider ll1c follow ing sb lemenls

For ;a lArgo Il\li.Jtiou gll!l turbin"'r nn ax ial

Oow eompressor is us u:JUy preferred O\'lll'"

e<m trifuga l compressorbecause

I. the maltimum efticicncy i8 higher;

2. Uu: f r o n I taeo .is luwc1.

3. the pressure nse per stage ;, more.

4. the cost is lower.

Which of the ~ ~ t e m ~ l w n above orecorrect. 7

a. I and 4

b. Only 1 and 2

c. L 2and 3

d. 2, 3 and .j

\Vhotare l.be general e<,>mfort c n n d i i ~ J ~ ~ lna.u •ir-oonditioni.ng sys[1.1u ?u. 20"CDDT. 80'loRH

b. 24"C DBT. 60°o RH

c.. 25°C DBT, 4()<!. RH

d. 25"CDBT. IOO"oRFI

Titc ben t lood .from the occupants in air

conditioning load ca lculation L• a source

of:

a, Sensible heat on ly

b. La tent heat on ly

o. Both sco.iblc o11d lntcutd. Noue ofd te above

\Vhnt is ohc s t : ~ ~ S i b l c hear tltctor during thehealing nnd lrurnidllication process e<tualto ''

I l l • li z

H, - I I ,

b.H

1- R,

!!, - H,

c. H,+ H,H, - H,

d.H, - H,

fi , - H,

\ V h e r c ~ H_a Tob l bea t of atr ~ J r i n g the

heating coil

H, Toul heat of nir l e o , ~ n g tbe healing

HJ : Toltll hent of air nt the end of th ebum idificatlon



w w

w . e x a

m r a c e

. c o m

76, \ \ ~ t u t is Sol-air cemp(wJturc ?

77

7N .

19

a. It fs cqunl '" the stun <lf omlloor nirlcmpernture, ond absorbed fotoJ

radiation d n ~ d e d by outer surtuccconvective hem transfer coefticient

b Tt equal tu the uilsorbcd totalra(limion •1iv idcd c ~ m v e c t f v ctransfer coctlicicnl at outer surfucc

c, It is equoJ to the total incident radiationdivided by convective beat transfer

c o ~ n i c i e r u ut oUiersurt:-.ce

d It i;; equal 10 the sum of indoor atr

tcmpemmre and nhsorbcd toWr!ldintion divided by conwctiw heattransl\:r coeflkienl at outer surface

Which t)'pl! nf vul\'eS is ge nerally used iureoiprocruing t•cfngcrnnt cumprcs.•or• ·)

a Mushroom valve

b Puppcr valve

c. Plull: valvc

d. TitrOIIIe valve

C o n ~ i d e r the f\llhJwfng stntcmcntspertaining to duct design

I. AspectralJO of dueL should be big.h .

2 lnlhe equul frictitllt mothtJd uf ~ ' i g nusc of damJlNS cannm be m i n m c dby any m ~ a n

3. The sta1ic r.:guin method is not suilablo

for long ducts.

.J The vclocit) r e d u c l ~ t ' n m ~ t h o d isemployed only in simp le systems.

Which of lhe srntcmcnts given ah(li'C

correct 7

a I and2

b. 3 :md 4

c. I and 3

d. land4

Mmch Lisl - I 'd th T st • II and select thec o r r ~ c answer using tJJc cOd'c give11 belowlhe Lists

List- I (Apparatus)

''" S<pnnrtiog calorimeter

B. Throttling a l o r i m t ~ t c rC. Sling psychrome1er

0 , Ga• thermometer

I isl - 11 ( nlcrm ud)'l11111lic pr!)CO:SS)

I Adiabatic process

80.

8L

M2.

83 .

f!J ot'JI

2 Isobaric proc<:SS

3. lr..1.:horic proces s.j lsenthalpic process

A 0 c na. I J 2 4

b. 2 4 3

" 4 2 3

d. l 3 4

A lhemJoelcc&ric engfne "h ich c o n s i s l ~ of

t\\'0 dissimilar dcctrk conduch1rscon nected at two junctions mointaincd nt

difli: rcnl lcmperalurcs. convcrls

a. Electric energy into heat energy

b. H<at energy inll' e ~ t r i c energy

c. Mcchanioal work into dcctrlc cntlfg)

d. Electric energy into mech anical work

4

p l

(kPa)2

A

I8

c

I I0 2 4 6 8 10 12 14

VOlume (ml )

\Vhoch nne or he following is the correcl

scq ueoocc Ql' Ute th.rcep m c c s s c . ~

A. B omd Con the i n c r ~ a . ~ i n ~ order of amount ofwork doo"' by n gas following idoal-gasexpansions by these processes o

H. A·ll-C

b 13-A-C

c. ,\.C-B

d C-A· Il

A Cnmot ref'ri!temtot ha; o COl' ot 6.Wbnl is the r a t i ~ uf lower 10 lhe i ~ l < ! rabsolute lempcra!Ures 1

D. t/(,

b. 7/8

c 617

d. 1n

A heat sour1.-e H1 cun SliP illy 6000 kJ/ mln

at 3oo•c and ru1ollter heat source ll2 cun1 1 p p l y 60000 kJ/min at 1oo•c Which

or Ute liJIIowing s t a t e m e n t ~ IS correct iflhc

surround n ~ me at 2 7°C ?



w w

w . e x a

m r a c e

. c o m

4.

87.

a, Bolh Ihe hea1 sources have We- s.nme

crrtcicnC)

b TI.e fir.ll heat sou.w has lo11errfficicnC)

c. The second heal source has lower

efficiency

d TI1e first he, l source prodtJoes hisJ.er

power

According lo the Clapeyron CqMtion,which one of' the following gives the. slopeof the sa turated liquid pressure

m p c m l l CIIIVC dp /dT/ (suffix I' and g

denote sa woalcd liquid and S>J iuralcd

vnpour leSpeclivcl)')

a, (u, - 111 )l(v, - 1·

1)

b. (11, - 111)t(v, - v1 )

c. (u. - 111)t[T(v - v1 ) ]

d. (h, -tr1 )1[1' (v, -vr }]

Wlud1 u11e of the foUowiug is thochnrnclenstic cquatioll Qf n ocal gns'l

a, (p - alv' ) (v- b) = RT

b (p - a!vl)(v +b) = RT

c. 17" =RT

d. pv= nRT

0 10

WbJcll one of the followmg ts com>c l lo r

the process 1-2 showu nbove ' 'a. The partial pressure of wntcr vapour fn

nir remains conslnnt

b. Specific 1iu111idity of air " ''""ius001lSl3.Ul

c. Ent halp)' of aor r e n ~ • i n s constanl

d. Dl)' bulb lt!lupomou•e of ait ~ m a ico11Siant

Cons1der Uoc foUowing stalcrneuts

]JCrtaming to the Clapey ron equallon .

$8.

89

\Ill.

lJ of HI. ll 1s useful to eshmnte properties like

cuthalpy from other measurable

properties.

2 At a change ofpllliSc. l l !U l be used tofind the latent hea t at a given press11te.

3. ll is dcnvcd fi·o"' the •fillatiotlship

(i'Jp) ~ )8v 1

; fl f •

Wlucb of lhc statcu1euts given above arc

coo:rect 'I

a 1 2and 3

b Ouly I and 2

c. Only I nnd '

d On]v 2 d ~A 12 em di.ao ueter suaiglu pipe is laid noaumfonu downgrade 11lld Oow rote IS

tnmntmncd snch l h ~ l vclocllv head in the

pipe is 11.5 m. l f he pressuro' ln the ptpe tsobserved to be uuifonn along u.e length

"hen the slope of the p1pe is I in IU wl. ,t is lhe f riclionl;,ctor lor the pipe '1

• . 0.(1 12

b. C U l lc. (),(142.

d. 0.051)

A ve.uurimeter '" an oil (sp, gr. 11.8) pipeIS I I I I C C ~ d lo 3 diffeccntial lllaJIOII\eiCr ill

which Ote gauge llquod is mercu1v

(sp, gr.13/il. Por flow rate of 11.16 nt1/s. the

rnlutonU> ter registers a gnugo ctiffcrenuru of

20 em . TI1c oil -mcJCUIY manometer beingunava,Jablc. nn air-oil differentialmanometer as connecte.d to the snme.

l'cntun meter. NeglccL111g \ ariat10 u of

discharge coefficocnt for d10 venl.lllimeteo·.

" hal IS IlK' IIC\\ .!f:UJl" diffCICIIIIal for nflm , mte o((UI8 111 Is 'I

a. 64 am

b. 68cm

c 80cm

d. 85 Cll l

:How nre the velOCity coefflcienl C.. the

discharge coefficient C.s, nnd thecontraction coefficient C, of au onfice

da. c . ; C.C.t

u. c, = c.cdc. C., ; cc.



w w

w . e x a

m r a c e

. c o m

•)I.

92 .

93.

'14-.

95.

d c.c,c,=1

Whkh one of the fc•l lcl\1 ing t f l l ~ l l l m i•

corrccl • While u$ing boundary l a y ~ requations. llcmoulli's equation

a, can be used y w e ~b. can be used on ly outside 1hc boundary

layer

c, can be used only onside the boundaryl•yer

d cannul bc used either inside or ouiSJdcche ooWJdruy laye r

l'hc vdodt) L ~ c r i b u t i n n in lite boundary~ y c r over a llat plate, parulh:l h i the

di•·ec t on <If m1 i n c o n p r c ~ ~ i b srreaoug1w n by pOwer law of t l • ~

torm u/U = (y/ll)1A What is tl1e rat iu of

displaccmcnc thicknc.<Q lQ boundar) la)crchickncss ')

a. I 8

b. I 7

c, 7 : 72

d 3 8

An open channel of symmctnc rig.hlnngled triangular cross- sectoon is

c o n ~ e n dischnrge Q. Taking ).!liS theacc.d eralion due to gruv1ly. ''jhnl is thtJ

critical dopth ?

a r ~ rb. ( 2 ~ rc. ( ~ rd l;'rIn M-1-T y s l e m whnt ls 01e dimcn<IClll o11'specific for " mtodyn amic pump 7a. L -l l• rJJl

b. M 11: L' 11 r mc. L1" r ~ ' : !d. L'"

In !he boundary layer. the flmv is

a. Vis cous and rotationnl

b luviscid tlnd lrmtationul

9b.

97.

98.

99.

c. lnv1scld aud rotational

d Vbcous and irrutouionnl

ur t I

II is observed in a flow problem , !halpressu re. inertia and gravity forces areimpootmot T similarity ~ q u i r !hat

a. Reynold• and W c b ~ r numbers cquol

b. Mnch ond Froudt numbers be equrol

c. Eiuler and Froude numbers be ec1ual

d. Reynolds und Much numbers be q u a lIn a nor0111l shock in a gas

a. Both the: downstream flow andupslrcam llow arc supersonic

b. Only lbc upstrcam now is supcrslln ic

c. The ilownstream now b so nic

d The upstream now is subSfmk

Tbe pressuro tl rop fn a pipe now is directly

prOiQI1ionalto the mean ' 'el<>oot,y It c.un bededuced lhat

a. Plow is laminar

b Flow is turhulent

c. l'ipe is

d. Pipe is rough

+

A circular jet of wnte.r im pinges on nvertical Oat p l o t ~ nnd bifurcates into tW<>

circular jets of half the dian•ctcr or lh t

vriginal. ,\ftcr hiuing the plate

a. jets move at q u u l ve locity whichis twice ofthe original w locity

b. The jets move nl equal ve locity whichis J tomes of tl1e original veloci ty

c. Daia given is iosufficient 10 t:alculatcvelocities of the two g o i n g j ~ t s

d j ~ L S m o ~ c 11 equal ' docity whichis equal to chc origonal velocity

I00. h is recommended that the difl'user aogleshnuld he keplle$5 th:UI I 8° because

a. f'rcssuo-.: decreases m now directionnnd tlo\\ separation may occur



w w

w . e x a

m r a c e

. c o m

b. l'res$ure decreases in flow direc-ionand now mny become turbulent

c. PreR§UI'\1 inc-rcnscs 10 flow direction

and flow separation m3)' occur

d_. P r e ~ s u r e increoses- in tlo.w direcrion

and flow may become turbulent

10 I A converging diverging nozzle l.

c.mnectcd 10 n gas pipeline. At the. Inlet oftbu nozzl<> (converging •oclion) the Machnumber is 2. It is observed that lll<>o is •

shock in the dwergmg section. Wbat is the-

vahtt f U t ~ M1ch numb.:r at lite throat ?

a "' I

b. E Q 1 1 ~ I

"" ,. 1

d. ~102 Which one of the f<•llt>wing is measured by

nr<1l;:J1tieta·?

a ·velocity of u i d ~b. Discharge ofOuids

c. ViscoRity of fluids

d. Rotntiunol speell <1f o l i d •ha (h

103. In o jet punlp

n. unctgy of Ooid i! couv..,rh;d

into potential energy

b. Energy of ltig_h velocity •trc:un ,.

converted inlo press ure energy

Energy of ltigh p r c ~ o u r o Ouio isconverted into energy of I0\1 pressurefluid

cl Potenti>l ene111y <>f ll11i<l ,. convertedinto lOneticenergy

HH Which of the following wnter tmbtnesdoes not require a draft tube 'I

Propeller turbine

b. Pelton turbine

~ KopiM turbine

d. Francis turbine105. Wbich u( following "ater turbiue.

1hni..ntain ltigh cfficicnc.>' ovcJ .1 longrange t)flhe p;o11lnncl 7

I . Fro.nci; tw·bine

2. !Coplon tllJ'bin"

3. Pelton lurbin"

4. P r ~ p e l l e r turbine

the cvrrect ~ n ~ w e r u.slng the codesg i v ~ n bclo\1

a. 1and 4

b. Only 2 and 3

<.:.. L2aud3

d. 2. 3 and 4

13ut l4

11>6. Whi"h of the following ~ d v a n t a g " " iFar"tWssessed b)' a KAt)lan turbine: uvcr •lintHt:.IS ~ ) i n c 'l

1. Low frictiou;ol loss.,s.

2. Pru1. toad e f f i . , i e n ~ y ;, consideral>ly

high.

3. More comp>cl ancJ smallor n site.

Select the correct a n ~ w e r u•ing th" code.given hcltJW

a. Only I

b. Only I and 2

c. Only 2 •ncl3

d. 1 2attd 3107. Effectiv.: tempCI'atur.: depends on dJ ) bulb

h!mpcraturtj. nod

a. \\lct bulb l < : m p r a l u r c only

b. Relauvc humidily

c. S p e < ~ i t l e humidity

d. Wet bulb temperature nod air mot ion

108. A humruJ body fcols oomforublo wh.m thoheat produced by U>e metabolism of

human body is equal to

a. Heatdissipated to the >!U ITOilndingsb. Heat •ttm:d in the hurn!ln bndy

c. Sum of L ond b.

d. Difference of o. and b.

109. In 4 vapmn Cl)mprcssiun refri!fer:ttionplaJil, tloc cntllnlt >Y values nl tliifl:l'<1ll

pointi are ;

I. Enlhalpy nl exit of !be evoporator •350 kJI\:g

2. Enthalpy ol oxil of the compressor 375

k.llka3. n U w l p y of he condenser = 225

kJikg

The refrigerating efficiency of the plant i•0.8. What is the power Te<Jtrired pcr k\\1 of

couling to be pruduccd'1

•· ozs ~ wb.

c. 12.5 k\V

d. llk\V



w w

w . e x a

m r a c e

. c o m

L10. Thy bulb lemperoture oml wet bulbtemp<.'1'3tllfc is 25•C .:.ch. and ve locity ol'

Air possing ovor human body 6 m m i ~ . II'

velocity increase.\ to 20 mimin. tltcn wltichone of l)lc fC>IIowing ill correct?

n, 1l1e effective e m p e r ~ t u r e ~ e r e o . ~ e •b. The effoolivc tcmpcmtluro remain.; lllo

N3111£f

c. l l1c effective tcmpcr.1turo incl'..:a:u.tt

d. Tile cbangc in ~ f f c c t i v e temper:•tureC'Jtutot be t>Stimoled wiU1 U1e giveuinformntion

I l l . TI1o wet hulh d c p r c s i• zc t'O, "hen

relxlive humidity e<[U:tllo :

IL Ill()"•

b. 60Uo

1:. 40''u

d. zer.,112. A . t m o s p h e ~ i c •lr ot 35"1 and 60% RH can

bebrought lo 20"C ond 60'lu RH by.

a. Cooling • nd dehnmidiiication rrocess

h C<1ol ing and hnmidification

<:. A d i o b ~ t t i c s• tur•tion proc...-u

d. Scnsiblo cooling process

113. Consider the followmg stolemenls :

Air w 1 1 . ~ h e r can wQ rk M

I HumidiJier only

2. DohumidiJior only

3. 'Filtc·• only

W11ich ofUte sl:il<>met•IS given Jll(lve is lo.reeorrc.:t 1

~ Only I

b. Unlv 2 and 3

c_ <)nly I anrl

d. 1. 2nnd 3

I 14. For small inslll llnt ion• of rcfrigcmtion

systems (up to ;.; k\1 ), which type ofcondenser is used ?

n. Shell •nd lube type

b. Shell coil type

c. Double tube type

d. Air cool.:d type

LJ5. In a vapour absorption r e f r i g e r . ~ t o r . heal i ;rtjo.oted in :

A. Condenser /lnly

h. Gencmtor only

l ln t l4

c. Absorber only

d. Condcn•er and absorb«

I 16. Wbdrc on nir 1 \ d ' r i g ~ r a l i o n cycle is

genera lly employ•'<!')

Domestic rcfiigcr•tor$

b. Commereial reliigcrall>l's

c. ;\j)·...:onditionutgd. Gas liq11ernction

117. A heaL pump is ~ e d co heat • house in thewin ter tmd then re\'er;;ed to cool the housein the summer. 'lltc i n ~ i d e lcmporot11re uf

the holL•c j.s lQ be m•intaincd 4L 20•c. 1l1cheat Iran• fer Utr<tugh the walt. is 7.9

kJ is and Ute outside temperature in will!«'is 5"C.

\VhM is the minhnum po1• er(npproximak) required tl.> tlrivc t.ltc he•(

pump1ll , 40.5 '\\'

b. 405 wc. .12.5 \V

d. 4'25 w118 . The 1ew in o refrigerAtion system Fre<>n

are detected by -

a. A halide Lorch , which on do1llcting

produces greenish !lame light

b. Sulphur sucks, which on detoc!ing give

the smokec. reagents

d. Sensing reduction in pressures.

I19. Whul is tlw value of the shape foetor of

two inJinne paro.llel s01foce •cparated by a

distanced 'I

a. ()

b. , ,

c.

d. ,,

120 It' the temlferature ot a ~ o i l siate- c h a n g e . ~from 17"C to 627"C. then emissive power

h ~ n g c which r a t ~ Ja. G. I

b. 9 : I

"- 17 · Id. : I

ies mechanical engineering paper 1 2006

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