Physics Stream (2012-July) Question Papers

USN fiPHYtA22

FirsUSecond Semester B.E. Degree Examination, Jtne 2Ol2

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B) longer than that of violet lightD) None of these

B) particle nature of IightD) None of these

B) Proton C) Alpha particle D) None of thesemoves in one-dimensional box of length 2nm, the normalization

A) Electroniv) If the electron

constant is

A) l(nm)-r12

Engineering Physics

Time: 3 hrs. Max. Marks: 100

Note: 1. Answer any FIVE full questions, choosing at lcast two frorn each part.L Answer all objective type questions only on OMR sheet page 5 of the answer booklet.3. Answer to objective type questions on sheets other than OMR will not be valued.4. Constants to be given, ma.ss of electron = 9.11 x lT3tkg, e = 7.6 x IUIeC,

c =3 xldm/s, h=6.626 xlo'3alS, k= 1.38 x1a23 J/k, t,=8.854 xlat2 F/m,Na = 6.022 x 1d6/K mole.

PART - AI a. Choose your answers for the following : (04 Marks)

i) U(traviolet catastrophe is the failure of Rayleigh-Jeans law in explaining theblack-body radiation for wavelength.A) equal to that in visible rangeC) shorter than that of violet light

iD Photo-electriceffectestablishesA) wave nature of lightC) dual nature of light

iiD Ifthe group velocity of the de-Broglie waves associated with a particle is 3 x l0a m/s,the velocity of the particle is

A) 3 x 108 m/s B) 3 x l0r2 m/s C) 3 x 104 m/s D) None of theseiv) The Compton wavelength is giv.en by

A; h/moc2 B) h2lm.c2 C) h/moc D\ h2l2m,cb. State de-Broglie hypothesis. Using the de-Broglie wavelength expression, show that an

alectron accelerated by a potential difference V vott is tr" = 'l.ZZ6 x lO-etJi . (05 Marks)c.d.

Define group velocity and obtain expression for the same. (06 Marks)Find the de-Broglie wavelength of an electron accelerated through a potential difference of182 volts and object of mass 1 kg moving with a speed of (l m/s) compare the results andcomment. (05 Marks)

2 a. Choose your answers for the following : (04 Marks)i) Ifthe uncertainity in momentum is large, the uncertainity in wavelength is

A) Small B) Large C) Tero D) None of theseii) Ifthe wave packet is narrow then there is

A) Large uncertainity in momentum B) Small uncertainity in momentumC) No uncertainity in momentum D) None of these

iii) An electron, a proton and an a-particle are enclosed in three one dimensional boxes ofthe same width. The energy levels will be closer together for

B) 2(nm) 1

I of 4

q kz,,l' D) None of these

L0PIIYt2t22

b. State Heisenberg's uncertainity principle. Using uncertainity principle explain thenon-existence ofelectron in the nucleus. (07 Marks)

c. Set up time independent Schrodinger wave equation for free particle in one-dimension usingcomplex variables. Write the expression for zero point energy. (05 Marks)

d. A particle,moving in one-dimension box is described by the wave function

v=xp:l for o<x<t and

V = 0 elsewhere

Find the probability of finding the particle within the interval | 0.;

I . (04 Marks)

3 a. Choose your answers for the following : (04 Marks)i) In classical free electron theory, the electric field due to ion cores.

A) is neglected B) is assumed to be periodicC) is assumed to be constant D) None ofthese

ii) Mobility of electron is

A) reciprocal of electrical conductivityB) acceleration ofelectron per unit ele. fieldC) average drift velocity per unit electric fieldD) None of these

iiD IfEF is the Fermi energy at absolute zero, then mean energy ofthe electron at absolutezero is

elE=r.sr, srE=ie, oE=3e, otE=]e"355iv) The resistivity of metals is due to scattering of electron by

A) phonons B) lattice imperfectionC) impurities D) All of these

b. Explain the termsi) Relaxation time; ii) Mean collision time; iii) Drift velocity (06 Marks)

c. Define Fermi energy. Discuss the Fermi factor f(o) for cases E < Ee, E > Er at T = 0, E =Eeat T + 0. (05 Marks)

d. Calculate the conductivity of sodium given r. = 2 x 10-raS. Density of sodium is 971kg/mt3. its atomic weight is 23 and has one conduction electrorl/atom. (05 Marks)

4 a. Choose your answers for the following : (04 Marks)i) The electric dipole moment per unit volume is

A) Magnetization B) Dipole momentC) Electric polarization D) Electric susceptibility.

iD The comparatively, high value oft, for water suggests that it isA) Semi conductor B) ConductorC) Di-electric D) Superconductor

iii) All materials have

A) Diamagnetic property B) Ferrimagnetic propertyC) Ferromegnetic property D) Paramagnetic property

iv) In ionic solid dielectric as the temperature increases the ionic polarizationA) Increases B) decreasesC) remain constant D) None of these

2ol 4

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b.c.d.

Derive Clausius-Mossotti equation.Describe any tkee polarization mechanisms with example.

B) incoherent lightD) None of these

B) high power pulsed laserD) low power pulsed laser

B) unlimited timeD) few milliseconds.

B) decreasesD) None of these

B) scatteringD) all the above

B) 1 of claddingD) AII of these

|$PHYt2t22

(05 Marks)(06 Marks)

(04 Marks)

(06 Marks)


An elemental solid containing 2 x lO28 atoms/mt3 shows an electronic polarizability of2 x '1040 Fmt2. Assuming a Lorentz force field to be operative, calculate the di-electricconstant ofthe material. (05 Marks)

PART-B5 a. Choose your answers for the following :

i) Spontaneous emission of light producesA) coherent lightC) unidirectional light

ii) The He-Ne laser is aA) high power continuous laserC) low power continuous laser

A) a few secondsC) a nanosecond

A) increasesC) remains same

iii) Attenuation in optic fibre is due toA) absorptionC) radiation loss

iv) Numerical aperture ofan optical fibre depends onA) acceptance angleC) q"o," of material

iii) The life time of an atom in a metastable state is of the order of

iv) From a broken hologram which is '10Vo of the original, if reconstruction of image isbeing done, thenA) onty l07o of information of the object can be obtained.B) complete information of the object is obtained.C) no information of the object can be obtained.D) None of these

b. Explain the termsi) Resonant cavity; ii) Metastable state; iii) Stimulated emission.

c. Describe the construction and working of He-Ne laser with the help of energy level diagram.(06 Marks)

d. The ratio of population of two energy levels is 1.059 x 10-30. Find the wavelength of lightemitted at 330K. (04 Marks)

6 a. Choose your answers for the following : (04 Marks)i) In a superconductor in superconducting state critical magnetic field

A) increases if temperature decreases B) increase with increase in temperatureC) does not depend on temperature D) remain content

iD If the optical fibre is kept in a medium of p > 1 instead of air, the acceptance angle

b.

d.

Discuss the different tlpes of optical fibres with suitable diagrams.Write a short note on Masslex vehicles.Calculate the N.A., V-number and number of modes in an optical fibre of core diameter50pm, core and cladding refractive indices 1.41 and 1.4 at wavelength 820 nm. (05 Marks)

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7 a- Choose your answers for the following : (04 Marks)i) A crystal oftetragonal lattice has

A) a=b=c B)a*b+c C)a--b+c D)a+b=cii) The relation between atomic radius r and lattice constant a in FCC structure is

A)a=2R nya=zJIR qu=4n ora=+n4J:iii) Packing factor of diamond crystal is

A) 34Ea B)527o C)68Vo D) 747oiv) Which of the following unit cells is a primitive cell?

A) Simple cubic B) bcc C) FCC D) None of theseb. Derive an expression for interplanar spacing in a cubic system. (05 Marks)c. Explain how Bragg's spectrometer is used for determination of interplanar spacing in a

crystal. (06 Marks)d. Calculat'e the energy of electron that produces Bragg's diffraction of first order at glancing

angle of 22o when incident on crystal with interplanar spacing of 1.8 Ao. (05 Marks)

8 a. Choose your answers for the following : (04 Marks)i) The nanostructure reduced in only one direction is known as

A) quantumdot B) quantum wireC) quantum well D) film

i, Fullerene is aA) molecule B) atomC) chemical mixture D) nano particle

iii) Testing ofa product without causing any damage is calledA) minute testing B) destructive testing' C) non-destructive testing D) random testing

iv) The signal due to a reflected wave is calledA) transmitted wave B) longitudinal waveC) echo D) peaco

b. With simple illustration describe the two methods of preparation of nano materials.(05 Marks)c. What are the potential applications of carbon nanotubes? (05 Marks)

d. Describe in brief a method of measuring velocity of ultrasonic waves in a liquid. (06 Marks)

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USN O6MAT11

First Semester B.E. Degree Examination, Jane 2Ol2Engineering Mathematics - I

Time: 3 hrs. Max. Marks:100

Note:l. Answer FIVE full questions choosing d.t least two from each pafi.2. Answer all objective type questions only on OMR sheet page 5 of the Answer Booklet.3. Answers to objective type questions on sheets other than OMR will not be valued.

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I a. Choose the correct answer :

i) The nth derivative of log[(3x + I )ee* * s] is

3'(-l)*r(n - l)! ,",3"t-l)"nl' (3x + I )"*'

(D) Zero.

tCrr!!de

(C) I2

(D) 1grd0

(D) I

(04 Marks)

(04 Marks)

(06 Marks)

(06 Marks)

((M Marks)

(A)

ii) If $ is the angle between radius vector and tangent to the curve r : f(0), then tan $ is

iii) If r = e0 at 0 = 0, then the slope ofthe curve is

(D%

(3x + l)"

(C) n!(-l)"' (3x + 1)'

(A) 1 do (B) r !9rdr dr

(A) 2u (B) uiii) Ifx: r cos 0, y = r sin 0, then

(A) 9t=-! (B) 9t=qdr */a* & dx

(A) 0

iv) The angle between the radius vector and tangent for the curve r = o e0 'ot o is

(A) I {B l+a (C) rFind the nth derivative ofe 3*

cos2 6x.

If y = tog11a tr[a ^1 , prove that (1+x2)y,*z + (2n+l )xy,+r * n2yn = g.

Find the pedal equation ofthe curve r* = a'(cos m 0 + sin m 0).

Choose the correct answer :

(C) 2x+2y (D) x +y

(D) a

b.

c.

d.

2a.

it Ifu=x2+y2then i'' ;. aqrr, ,o' A*6y(A) 2 (B) 0

iir ltu=,", fLl.,n.n* 1*v9 isequat ro"(yl 0x'6y(c) 0 (D) I

(C) 4=0 tD) None oftheseAr

iv) Ifan error of l7o is made in measuring its length and breadth, the percentage error inthe area of a rectangle is

(C) '027o (D\ l7o1of 4

\A) .2?o (B) 2qo

u. Ir, = t""'($) n.ou" ttut *4*rfr =]'i, 2,.

c. tf z=f1x, yr. x = e'+ e' and y = e-'+ eu, show that ?-?--?-r* 106Mar&sr' au dv dx 'Ay

d. If u= x+y+z.v=x2+ y2+r' . * =xy +yz+zx. findl[u.''w). (06 MarksrI ^,y.. J

a. Choose the correct answer : ((X Marks)n/

i) The value of f '

cos, xdx is-h

(A) 14 (s) i2 (c) Zero e) l:135 35 128

ii.1 The value of f' n. ,, dx is

b 1l + x, )/2

(A)

iii)

(A)(c)

iv)

(A) 2loe2

(B)2l5

(B) 2 log 2-1

(c) :1l5

(B) the pole(D) None of these.

O6MAT11

(04 Marhs)

@) l:2

/r\tD)loslal'[e/

((N Ma*s)

(06 Marks)

(06 Marks)

(04 Marks)

4

GIf the equation ofthe curve remains unchanged after changing 0 by -0, the curver: f(0) is symmetrical aboutInitial lineSymmetry does not exist

I tant odo =J0

1Ct 1t2log 2-ly

b. Obtain the reduction formula for Jsec"

xdx.

c. Evaluate I x,J2ax-*, dx.f)

d. 'Trace the curve a2y2 = x21g,2 - x.z).

a. Choose the correct answer:

i) lfr = f(0) be the polar curve. th"n S i,dr

(A' [,,.(edJ

(O fvo*

'4 b"t*""nx = I andx=4isThe length of the cuwe y = y *)

?g,t *rr.1 6 ?$z -2xl Gt ?st5.1 :r

i9 g If r1-,"px] iseeualto

(A) f 9rt*, ora*t dcl

to fartx,clao

(D) None of these

ii) The area bounded by the curve y = f(x), the x - axis and the ordinate x = a and x = b is

ta) Iyav rnr frax(D) None of these

iii)

(A) @) Zzt

(B) lan*. ou*.l da(D) None of these.

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c. Find the surface ofthe solid formed by revolving the cardiode r = a(1+cos 0) about theinitial line.

b. If x =aeisint, y= ae'cost,find *.

Solve (l+ "%1dx+ "t

(t - *ty) oy -- u.

(D) y-x=viv) The equation y - 2x = c represents the orthogonal trajectories of the family(A) y=ae2* (B) x+2y=c (C) xy=a (D) x2+2y2=a

1/(C) e t*

(B) Divergent(D) Oscillatory.

O6MAT11

((X Marks)

(04 Mad(s)

(D) None of these

(D) None of these

(M Marks)

(06 Marks)

(06 Marts)

(04 Marks)

(04 Marks)

(0,6 Marks)

d. Evaluatef,g'(l-e "-)dx,whenc > -1 by differentiating under the integral sign. (06 Mart<s)

(06 Marks)

PART. Ba. Choose the correct answer:

i) The general solution ofxdy- ydx = 0 is(A) x+y=s (B) xy=c (C) y=xc

ii) The integrating factor of the differential equation *' !I + y = l is'dx

+ (B) toe xx

The homogeneous differential equation M(xy) dx + N(xy) dy = g san be reduced to adifferential equation in which the variables are separated by the substitution

(A) x+y=v (B) x = v/y (C) y=vx

b. Solve cos(x+y+l) dx - dy = 0.

(A)

iii)

c.d.

family of cardiod e r =b sin2 (%).

a. Choose the correct answer :

(A) Convergent(C) Either convergent or divergent

Show that the orthogonal trajectories of the family of cardiode r = a c osz (f) is another

i) Let Iu, be a series of +ve terms. Given that Iun is convergent and u;.o 1i.14g1is6sn_- Un

. then the said limit is(A) Necessarily equal to one (B) Necessarily greater than one(C) May be equal to one or less than one (D) Necessarily less than one.

.)1t5lll I ne Serles :*-:+----a+ lslj ,j ']r 4: '""'

(A) Conditionally convergent (B) Absolutely convergent(C) Divergent (D) None of these.iii) Which one of the following series is not convergent?

tnr -L+-L*-L*.....2.12 3J3 4J4(B) 1-1+1-q+.....

2345

tcl l-1-1-1. (D) x + x2 + x3+ .... where lxl < l.23 4 5

iv) If Iun is +ve term infinite series and if lim u, = 0, then Iu, is

b. Find the nature ofthe series 2 * 4 * 6 *.....

1.2.3 2.3.4 3.4.5

c. Test for convergence of the ss1;gs ; 1a 1

x 1i 6 x211!2*3....... , 1v g.7 7.tO 7 .4.5

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Define absolute convergence and conditional convergence. Is the series

,- | - | | - conditionallyconvergenl.?' zTz-iTt-iTq-'Choose the conect answer :

lltrCr x-l y-b z-c

loo

(A) 4x-32+2xz(C) z(xi+4yj+3zk)

0llrllt x-a _ y-b z-c

001

(B) xi+yj+zk(D) None of these.

O6MAT11

(06 Marks)

(04 Marks)

(06 Marks)

(04 Marks)

(06 Marks)

i) Ifcos o , cos B , cos y be the direction ratios ofthe line, then sin:a + sin2p + sin2y =(A) z (B) 6 (c) 4 (D) 8

ii) The angle between the two planes 2x - y - 32 = 5 and x +3y-22+6=0is(A) 600 (B) 9oo (C) cos '1 s ;

t4(D) None of these

iii) The angle between any two diagonals ofa cube is

(N % 181 tan't( /r'1 G) cot't( N) @) colt1/yiv) The equation ofa straight line parallel to the x - axis is given by

(A) x-a-y-b-z-c 13) x-a - Y-b z-c

b. Find the value ofk, such that the set of four points (l,l,0), (1,2,1), (4,5,6) and (3,0,k) arecoplandr. (04 Ma*s)

c. Find the equation of the plane passing through the line of intersection of the plane

2x+y-z= l,5x-3y+ 4z+3 =O and parallel to the 11n" x-l-v-2-z-3. (06 Mart<s)234Find the shortest distance and its equation between the lines *=5=i *Ox _y-9-3 2

z-2

8 a. Choose the correct answer :

i) The angle between the two surfaces $ (x,y,z) and ry(x,y,z) at any point (xr,yt,zr) is 0 -141 51n-r(v6.vv)

l.lvolivql',",,un-r1v6.vy)

li"oli"ti]

(B) Cos-r f vo.vv lll"dF',ll

(D) None of these

A unit tangent vectortothe surface x = t, y = 12. z = tJ at t= l.(y, x y,l 1g1 (r : r.)

1.,'i' fi fil(C) (."6, ,.,6.,./[) (D) None of these

iii) If A = 2x2i - 3yzj + xz2 k, then V.A is

iD

(A)

iv) For any scalar $(x,y,z), the value of VxV{ is(A) I (B) 0 (C) 2 (D) None of these

b. Find the directional derivative of{ = x2yz + 4xz2 at the point (1, -2, -l) in the direction ofthe vector 2i-j - 2k. (M Marks)

c. If A is a vector function and Q is a scalar function then prove that

Curl (Q.I)=0(curl I)+gradSx Ld. Find the constants a and b, so that F = laxy + z3)i + (3x2 - z)j + (bxz2 - y)k is irrotational

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and find $ such that F= V0. (06 Marks)

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USN 1OMAT2l


(04 Marks)

Second Semester B.E. Degree Examination. Jane 2Ol2Engineering Mathematics - II


Note: 1. Answer FIVE full questions choosing at least two from each part.Z Answer all objective type questions only on OMR sheet page 5 of the answer booklet.3. Answer to objective tjpe questians on sheets other than OMR will not be valued.

PART-A

1. a. Select the correct answcr : (04 Marks)i) We say that the given differential equation is solvable for x, if it is possible to

express x interms ofA) x andy B) -xandp C) yandp

ii) The general solution of P2 - 7P + 12=0isA) (y+3x-c)(y+4x-c)=0C) (y-4x)(y+3x)=0

D) x,yandp

B) (y-3x-c)(y-4x-c)=0D) None of these

B) y=3x+log(3+ceY)D) None of these

iii) The general solution of the equation y = 3x + log P isA) Y=:x+3+ceYC) y+3x= 3+cey

iv) The general solution of the equation (y - Px)2 = 4P2 + 9 is

A) y=cx+ B) Y="+

b.c.d.

C) y=c x+.[aS-g D) y-c x=4c2+9Solve: p2+ 2pycotx=y2.Solve : p2 + 4 xsp - l2xa y = 9, q61a1, the singular solution also.

2.

. Solve the equation (px - yt (py + x) = 2p by reducing into Clairaut's form, taking thesubstitution X= x'. Y =y". (06 Marks)

a. Select fte correct answer :

i) P.L of y" - 3y' +2y : 12is

A) 6 B)y=cre*+c2e2* C) | D)'12ii) The complementary function of (Da - aal y = 6 ;5

A) y = c r eu' + c2 e-u* + ca cos x +c4sin xB) Y = cr e-u* + c2 e"*C) y = c, eut + c2 e-u* + ca cos ax + c4 sin axD) None of these

iii.) If F(D) = D2 + 5, I s,in 2x= .......f (D)

A) -cos 2x B) cos 2x C) sin 2x22iv) The solution of the differential equation y" - 3y' + 2y : s3* it

I

i

D) cos 2x

A) y=cr e-*+c2e2*+ !;*

C) v = c, e-* + c, e2* + 1eJ*-2

B) v=c,e'+c,e2*+ lei*2

D) v=cre'*+cre2*+ 1el*2

4c2 +9 4c2 +9

l of 5

lOMAT2T

b. Solve : (D -2)2 y=8(e2'+sin2x). (0s Marks)c. Solve : y" - 2y' + y : x cos x. (05 Marks)

d. Solve *-Zy =.o"Zt, $+2x =sin 2t,giventhatx= l,y=0atr=0. (06 Marks)dr"dt

3. a. Select the correct answer : (04 Marks)i) The Wronskian of x and e* is

A) e*(1-x) B) xe* C) e-x(x-l) D) e- (x-l)

ii) In the equation #* r= sint+ 1, 9I* * ="o, t, if y= sin t+ I + e'r, then x = ....

A) 0 B) e-t C) x e-t D) e'iii) In homogeneous linear differential equation whose auxiliary equation has roots

l, -l isA) y" +y:oC) x2y"+xy'- y=Q

iv) The solution of x2 y" + xy' = 0 isA) y=cr+c2 logx B) y=atogx+6 C) y=gr D) y=e-t

b. Using the method of variation of parameters solve y" + 4y = tan 2x. (05 Marks)c. Solve: (l+x)2y"+ (1+x)y'+y=2 sin flog(1 +x)]. (0s Marks)

and b isA) z=px+qyC) z=px+qy-pq

B) x2y"-xy'-y=0D) y"-y':o

B) z=px+qy+pqD) z=px-qy-pq

d. Solve by Frobenius method, the equation

4* d'X*2dY*r=t.t.dx' dx

4. a. Select the correct answer :

(06 Marks)

(04 Marks)

^ 6'zi) The solution of - ; = sin (xy) is' Dv'

A) z= -x2.int*Vl * yf(x)+g (x) B) z= 99s(ID.+ y f(x) + Q (x)x-

C) z=- sin( Iy) + y f(x) + 0 (x) D) None ofrhesex-

ii) A solution of (y-z\p+(z-x)q=x-yisA) x2+ Vi+z!= f (x+y+z) B) x'- y'-r'=f (x-y+z)C) x'-y'-z'=f(x-y-z) D) None ofthese

iii) The partial differential equation obtained form z = ax + by + ab by eliminating a

iv) The partial differential equation obtained from z = f(x + y) + g(x - y) byeliminating the arbitrary functions isA) r+t=0 B) r-t=0 C) r-a2t=0 D) r+a2t=0

b. Solve !1*r=g,giurnthatwhenx =Q,2=gt N6 I =1. (05 Marks)0x' " dxc. Solve : (x2 - yz) p + (y2 - zx) q-- z2 - xy. (05 Marks)

d. Solve by the method of variables + $ * I = .lr, given that u(0, y) = 2 esv.ax dy(06 Marks)

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PART -B

1OMAT21

(04 Marks)5. a. Select the correct answer :

i) The vatue of l' l' * n' o* o, i,.t.lc) ll'2

ii) The integral f i ;* dx afterchangingtheorderof integration is

-6 .v -_vA) [lao*o, B) f fl:]*0,t "0 y t'y yp p -, .@ -! 6-yC) I I :-dx dy D) | | :ax aytb y tt y

iii, s [1.])=.....' l) )l.T

A) G ,, * c) 3.1416 D) -n

iv) In terms of Beta tunction f .,"'rJ* d0 = ........

A) p@,1) u )o<+,lt c) pe,})"> f,o<r,|t

)b. Change the order ofintegration in

I'o {*

y'dx dy and hence evaluate the same.

c.' Evaluate { f f.' e**Y*'dzdydx.

d. Showthat fJsine * fJ*,, or=,.

a. Select the correct answer :

i) In Green's theorem in the plane {m

dx +n dy= ......

A) filf. , e

]a* a, B) ti[!ln-4')d. o,' r^r[ ay ox )"" "' lrl ay a* )"" "'

., I(*-#).. * c) lfF. a o.

ii) The area of the eltipse i. # = t by emptoying Green's theorem is

B)l

(05 Marks)

(05 Marks)

(06 Marks)

(04 Marks)

A)0 B)1 C)n D) r abiii) A necessary and sufficient condition that the line integral JF. dR forevery closed

L

curve C is

A) curlF=0 B) divF=0 C) curlF=O D) divF-03 of 5

A)0 D) 13

1OMAT21

iv) If V is the volume bounded by a surface S and F is continuously differentiablevector tunction rhen fff Oi" F dv = .....

A) { F.di B) [[F. n a, c) fftv*n).n os D) Noneof these. J JJ )J'essb. If F = 2x y i + yz2 j + x z k and s is the rectangular parallelepiped bounded by x = 0,

y=0,2=0, x=2,y=1,2=3,evahate lJF. n O'.s

c. Using Green's theorem, evaluate Jt(V - sin x)Ox + cos x dy J, where C is the planec

triangleenclosed by the lines y =0. x = I*Ot = ?.d. VeriSr Stoke's theorem for fr =1x2+ y21i-Zxy l taken around the rectangle

(05 Marks)

(05 Marks)

bounded bY the lines x = + n, Y = Q, Y = [.


i) L {e2o-1)1 ='...

A) I B, "-'' s-2 s-2ii; I 1th1 =.......

-rA)g rl,21:./, ,/,

.... - [sin tlur) L<->= ......trlA) I+tan-r s B) 1 - .ot-' ,22iv) L {6 (t+ 2)} = ......

(06 Marks)

(04 Marks)

,, ;',

o) rr_2s/2

D) tan-1 s

D) eu'

(05 Marks)

(05 Marks)

. (06 Marks)

(04 Marks)

D) asin h: t

c)ls+2

c) J;,G

A) e-u' B) e2'

C) cot-1 s

c) e-2'

b. Find the value of l" C.-' sin t dt using Laplace transforms.+

Draw the graph of the periodic functionI t O<t<rr

f(tl = i and find its Laplace trans [orm.|.n-t. ,r<t<2rr

Prove thatL [6[t-a)J =e''.

Select the correct answer :

i, t,l--Ll,=las' - 36J

A) lcos h 6t B) I sin 3t'4 12

ii) Ir{l+e"}=Is')

A) t+(t-3)u(t-3)C) t-(t-3)u(t-3)

d.

8. ^.

c) *to'n r'

B) (t-3)u(t-3)D) t+(t+3)u(t+3)

4of5

1OMAT21

iii) L'l lcor' 1I=' t a)

O, sin t B) .in, I sin h a t ,, sinh tt t' , t

iv) L[{ rtrts(t-u)du]

A) f(t)g(t) B) f(s)g(s) c) f(s)-g(s) ,, Hb. Find'{ed:*-} (osMarks)

c. Apply convolution theorem to evaluate

-,1 s2 I

' {5';,x;-g} (osMarks)

d. Solve (D3 - 3D2 + 3D - 1) y = t2 e'. y(0) = l. y'(0) = 9, y" (O) = -2by Laplacetransform method, (06 Marks)

5 of 5

USN

B) Arch bridge

B) StructuralEngineeringD) Surveying

10crvl3/23

(04 Marks)

(06 Marks)(06 Marks)(04 Marks)

((X Marks)

FirsUSecond Semester B.E. Degree Examination, Jane 2Ol2Elements of Givi! Engineering and Engineering Mechanics


Note: 1. Azsyer FIVE full questions choosing at least two Irom each part-2. Answer all objective type questions only on oMR sheet page 5 of the answer booklet.3. Answer to objective qpe questions on sheets other than oMR will not be valued.

PART-A

l. a. Select the correct answer :

i) A Bascule bridge is aA) Floating bridgeC) Suspension bridge D) Movable bridge

ii) Geotechnical engineering involves the study ofA) Water B) Soil c) Air D) All of rhese

iii) Pick up a structure in which an inspection gallery is formedA) Dam B) Bridge C) Harbour D) Airporr

iv) The part ofcivil engineering which deals with waste water and solid waste is called

b. Explain the role ofcivil engineer in the infra - structural development ofa nation.

A) Transportation EngineeringC) SanitaryEngineering

A) Translatory effectC) Both A and B

ii) Effect of force on a body depends onA) Magnitude B) Direction

B) Rotational effectD) None of these

C) Position

c. Explain different types ofroads.d. Give the difference between Earthen dam and gravity dam.


i) The moment of a force about a moment centre is a measure of its

D) All of theseiii) Couple means two forces acting parallel and

A) Equal in magnitude and in same directionB) Not equal in magnitude but in same directionC) Equal in magnitude but opposite in directionD) None of these

iv) The magnitude of the moment is _ when a force is applied perpendicular toa leverA) Maximum B) Minimum C) Zero

c. Explain equivalent force - couple system. (04 Marks)d. Determine angle 0 ( 0 < 0 < 1800) for the force F = 200N shown in fig.e2(d), so that it

produces (a) maximum moment about .A, and (b) minimum moment about .A,.

b. State and explain principle of transmissibility ofa force.

Determine maximum and minimum moments.I of 5

D) Negative(04 Marks)

(08 Marks)


i) The process offinding the resultant ofa system of forces is called

Fie.Q3(b)

A) Resultant B) Resolution C) Composition D) None of these

ii) If two forces P and Q (P > Q) act on the same straight line but in opposite directiontheir resultant is

u, ; c) Q-P

t0ctvt3t23

(04 Marks)

D) P_Q

D) None of these

A) P+Q

iii) Component of a force at a right angles to its line of action is

A) Tero B) Positive C) Negativeiv) In a coplanar concurrent force system if XH : 0, then the resultant is

A) Horizontal B) Vertical C) Moment D) None of these

b. The 26kN force is the resultant of two forces, one of which is shown in fig.Q3(b).Determine the other force. (08 Marks)

Y^f

'f-

c. A rigid plate is subjected to the forces as shown in fig.Q3(c), compute resultant offorces and position of resultant force with respect to centroid point '0' of the plate.


(08 Marks)

(04 Marks)

i) Centroid of semicircle of radius 'R' about its centroidal axis parallel to diametricaxis is

3R B)E c) 4R

4x 8t ItAn axis over which one half of plane figure

'l

Il.2or,(

II nie.e:t"r

_4RD) ;-J7T

is just mirror image of the other

A)

ii)half is

A) Axis of symmetryC) Bottom most axis

iii) Moment oftotal area about its centroidal axis is

B) Unsymmetrical axisD) None of these

B) Three times the area

C) None of theseA) Twice the area

C) Z,eroiv) The centroid ofa triangular lamina of height 'h' is situated at a distance

- from

its apex.h

A)3

B)?! c) !5L

2of5

,r+

5;olor

tocrvt3t23

Locate the centroid ofthe shaded area shown in fig.Q4(b), with respect to point '0'.(08 Marks)

I*'kry

IrrlF_6oc

PART. B5. a. Select the correct answer :

i) The force which is equal and opposite to resultant is

c. The centroid of the rectangular area requires to be shifted from point '0' to 01 (2 cms).This is accomplished by removing hatch portion which is l2cm deep and symmetricalabout X X-axis. Determine area of hatched portion shown in fig.Q4(c). (08 Marks)

A) Resultant forceC) Equilibrant

b.

Fie.Q4(c)

(04 Marks)

B) MomentD) None of these

ii) A particle acted upon by the two forces of equal magnitude is in equilibrium. Theangle between the forces isA) 0o B) 9oo c) r800 D) 450

iii) The necessary condition of equilibrium of a coplanar concurrent force system isalgebraic sum of must be zero.A) Horizontal and Vertical forces B) Moment of forcesC) Horizontal vertical and moment of forcesD) None of these

iv) Lami's equation can be applied when number of unknown forces are _A) TWO B) Five

b. Determine the angle 0 for theC) Four D) Three

system of strings ABCD in equilibrium as shown in(08 Marks)

Fie.Qs(b)Fig.Qs(c)

A cylinder of weight 600N rests on smooth surfaces as shown in fig. Q5(c). Determinethe reactions at contact points. The contact surfaces are perpendicular to each other.

(08 Marks)

(04 Marks)6. a. Select the correct answer:i) A cantilever beam is one in which

A) Both ends are fixed B) Both ends are hingedC) One end is fixed and other end is simply supportedD) One end is fixed and other end is free.

I

I

t",rI

3 of 5

ii) A truss is perfect whenA) m=2j-3 B) 2j=rna3 C) m=3j-Z

iii) The minimum number of members to form a perfect truss isA)l

A) zero B) 2 c)3


i) Compared to static friction, kinetic friction isA) greater B) smaller C) very large D) zero

State laws of static friction.Briefly explain i) Angle of repose ii) Cone of ftiction.

induce slipping. Take p = 6.25 for all contact surfaces.


t0crYt3t23

D) 2j=6-3

D)4B)2 c)3iv) The number of reaction components at an hinged end of a beam

D)lb. A pin joined truss is loaded and supported as shown infig.Q6(b). Determine forces in

members BC, GF and CG and nature of forces. Use method of section. (08 Marks)

ri KN

Fie.Q6(b) Fig.Q6(c)

c.E

Find the reactions for the beam supported and loaded as shown in fig.Q6(c).(0s Marks)

5lr

IIr

1 (M Marks)

((X Marks)(04 Marks)

(08 Marks)

(04 Marks)

ii) Frictional force acts _ to the surfaces in contactA) Tangential B) Normal

iii) The force of fiiction depends onA) Area of contact

C) Inclined D) None of these

B) Roughness of surfacesC) Both area of contact and roughness of surfacesD) None of these

iv) At the point of impending motion, the static flictional force isA) Zero B) Maximum C) Minimum D) Infinite

b.c.d. A ladder 7m long weighing 300N is resting against a wall at an angle of 600 to the

horizontal ground. A man weighing 700N climbs the ladder, at what position does he

8.i) Moment of inertia of a square of side 'b' about an axis through its centroid is

ii) Moment of inertia of a triangle of base 'b' and height 'h' about its base is

A)4t2

A) K-=K*+Kyyq K'z- = rl-+ r'z,

c){36

c)ql2

C) KN- m

B){8

D){l2

D) Bh,t2

D) mma

A) lli B) !436 36iii) The unit ofradius of gyration is

A) mm B1 mmziv) Which of the following equation relating to radii of gyration is correct?

B) K--=&v+K-D) None of these

4of5

IOKN

4i ,\

t0crvt3t23

(06 Marks)b.c. Determine moment of inertia and radius of gyration of the area shown in fig.Q8(c),

State and prove parallel axis theorem.

about base AB and centroidal axis parallel to AB. (10 Marks)

Fie.Q8(c)

5 of 5

a

t:e

o.. tt

H"o.E c't

ctro,

=.99?E

.gd

->a

o, 6-

6.J

qE;E

6i

o<-i di

z

E

FirsUSecond Semester B.E. Degree Examination, June 2Ol2Elements of Givil Engineering and Engineering Mechanics


Note: l. Answer any FIVE full questions, choosing at least two frorn each part.Z Answer all objective Epe questions only OMR sheet, page 5, of the answer booklet.3. Answers for objective type questions on sheets other than OMR will not be valued.4. Missing data if any may be suitably assumed.

C) Shoulders D) Fencing

B) Through bridgeD) None of these

B) Inigation engineeringD) Hydraulics

06cl-t3t23

(04 Marks)

(06 Marks)(06 Marks)(04 Marks)

(04 Marks)

D) Rigid body


(08 Marks)

PART - A

I a. Choose your answers for the following :

i) Temporary dams are called as

A) Traffic seperators B) KerbsiiD Bascule bridge is a

A) Deck bridgeC) Semi-through bridge

iv) Geo-technical engineering is also called as

A) Structural engineeringC) Soil mechanics

A) Rotational effectC) Irrotational effect

A) Earth dam B) Gravity dam C) Coffer dam D) Diversion dam.iD Boundary between carriage way and foot paths are

b. Explain impact of infrastructural facilities on socio - economic development of a country.

c. Explain briefly with neat sketches, gravity dam and earth dam.d. Draw simple sketch ofany two types ofbridges.

2 a. Choose your answers for the following :

i) An object which has only mass, but no size is calledA) Continuum B) Point force C) Particle

iD Moment of a force about a point is a measure of itsB) Translational effectD) None of these.

iii) A body which does not under go any deformation on application of force is

A) Deformable body B) Rigid body C) Elastic body D) Plastic bodyiv) Two equal and opposite, parallel and non-collinear force constitute a

A) Point force B) Couple C) Both A and B D) None ofthese.b. Write any two Newton's laws of motion. What are the characteristics of a couple?

c.

d.State and explain the principle of transmissibility of a force.A system of forces is acting on a rigid body as shown in Fig. Q2(d), reduce this system toi) a single forceii) a single force and a couple at Aiii) a single force and a couple at B.

Fig. Q2(d)I of 4

06ctYt3t233 a- Choose your answers for the following : (04 Marks)

i) Lines of action of all forces pass through a single point and all forces lie in the sameplane. Such forces are called

A) Coplanar concurrent forcesC) Non coplanar concurrent forces

iD The method to resolve a single force in two mutual perpendicular directions is called

t'op.'oortx

iii) Resultant of two forces shown in Fig. Q3(a) isA) 1000 kN B) l400kN c) llo0kN

Fig. Q3(a) Fig. 3(b) Fig. Q3(c)iv) Two forces of equal magnitude P act at angle '0' to each other. What will be their

resultant?A) Pcos 0/2 B) 2Pcos0 C) 2Pcos 0/2 D) Pcos0.

Two forces acting on a body are 500 N and 1000 N as shown in Fig. Q3(b). Determine thethird force F such that the resultant of all three forces is 1000 N directed at 45o to thex-axis. (06 Marks)Find the equilibrant with respect to A as origin for the system of forces shown inFig. Q 3(c). (10 Marks)

Choose your answers for the following :

i) Point where the whole weight of body acts at

(04 Marks)

A) Composition of forcesC) Moment

B) Coplanar non concurrent forcesD) Collinear forces.

B) Resolution of forcesD) All of the above

B) Centre of gravityD) Second moment of area

",+ D)

B) Right angled triangleD) Equilateral triangle

A

h.

c.

4a.

iD The distance of centroid of quarter circle from its diameters are

A) CentroidC) Axis of reference

A)g)71

A) CircleC) Rectangle

B)r 3r

4triii) Height of centroid ofa triangle ofheight 'h' from its base iso,+ nr]rr ., 1 ,,+iv) The centroid of a plane lamina will not be at its geometrical centre if it is a

b. Locate the centroid of a semicircle by the method of integration.c. Locate the centroid of the shaded area shown in Fig. Q4(c).


D) l200kN

2of4Fie. Q4(c)

PART - B5 a. Choose your answers for the following :

i) Relation between action and reaction force is

A)They are equal in magnitude and opposite in directionB) They have common line of actionC) Act perpendicular to the line of contactD) All the above

ii) The non-applied forces areA) Self weight B) Reaction

06ctvt3t23

(04 Marks)

b.c.

iii) A force which nullifies the effect of forces is calledA) Equilibrium B) Equilibrant C) Resultant

iv) A system that possesses a resultant

C) Both A and B D) None ofthese

D) None of these

B) Will be under restD) None of these

(02 Marks)

B) Simply supported beamD) Cantilever beam

B) Uniformly varying loadD) General loading

B) Simply supported beamD) Continuous beam

A) Will be in equilibriumC) Not be in equilibrium

State Lami's theorem.

A) Fixed beamC) Propped cantilever beam

A) Uniformly distributed loadC) Moment

iii) A statically indelerminate beam is aA) Cantilever beamC) Double over hanging beam

d.

6a.

A sphere of weight 5 kN is supported by the Pully 'P' and 2 kN weight passing over asmooth pully as shown in Fig. Q5(c). If o = 30', calculate the value of P and 0. (06 Marks)

Fig. Q5(c) Fie. Qs(d)

, 4nuA string is subjected to the forces 4 kN and P as shown in Fig. Q5(d). Determine themagnitudes of P and tension forces induced in various portions of the string. (08 Marks)

Choose your answers for the following : (04 Marks)i) A beam which has one end fixed and other end simply supported is called

iD Ifthe intensity of load increases linearly along the length ofbeam, it is

iv) A support, where two reaction components exist which are mutually perpendicular, isA) Simple support B) Roller suppot C) Hinge support D) Fixed support.

b. Find the suppo( reaction for the cantilever beam loaded as shown in Fig. Q6(b). (os urarts)

k 5h;+- 5m _?k* 4m -r+ _ _4h , k_1m _r+-_ 3n______?t_, r,5mJ

Fig. Q6(b) Fie. e6(C)c. Determine the reaction at the supports A and B for a beam loaded as shown in Fig. e6(c).

3 0f 4 (08 Marks)

k-1m +- 3llr-----,r+-, t,5mJ

Fie. Q6(C)

7a. Choose your answers for the following :

i) Friction acting on a body which isjust on the point or verge of sliding is called

Define: i) Angle of fiiction ii) Co-efficient of striction.A block weighting l0 kN is to be raised by means of 20oFind the horizontal force P, which will just raise the block.for all surfaces of contact is 0.3. Neglect weight of wedge.

06crYt3t23(04 Marks)


wedge as shown in Fig. Q7(d).Assume co-efficient of friction

(10 Marks)

iD Friction acting on a body when the contact surfaces are completely separated bylubricant is called.A) Non viscous fiiction B) Film fiiction

iii) Friction force always actsA) Opposite to the motion of the bodyC) Peryendicular to the motion

iv) The coefficient of friction is equal toA) The tangent ol cone of flictionC) The tangent of angle of repose

State the laws of fiiction

A) Limiting frictionC) Co-efficient of friction

B) Sliding frictionD) Cone friction

Viscous friction D) Dry friction

Along the motion of the bodyNone of these

B) The tangent of angle of fiictionD) The ratio of resultant to normal.

c)

B)D)

b.c.d.

Fie. Q7(d)


i) Area moment of inertia isA) First moment of areaC) Radius of gyration

iD Radius of Gyration is given by

((X Marks)

Second moment of areaArea of cross section

B)D)

A) K=# B)K=F c) K=

oq'48of elemental areas of plane

D) K=IxA

D)u-16

figures about centroidal

iii) Moment of inertia of a triangle about its base is

bhlA) Dn B) -36 t2

iv) Algebraic sum of first momentaxis is alwaysA) UnityC) Total area of elements

B) 7,eroD) Moment of inertia.

b. State and prove perpendicular axis theorem. (04 Marks)c. Determine the second moment ofarea and radius of gyration about the horizontal centroidal

axis for the shaded area shown in Fig. Q8(c). (12 Marks)

Rr = 20 mm,Rz = 50 mm,Rr = Radius of circle,Rz = Radius of semi circle

4of4

1

I

+

Fie. Q8(c)

: ,,8 Ia. =t =' :? 5ll I "r

,i,r;iee3;iri'a! iii st-#.;q;es!': Zi x.i.q df"3Eir-; 43 E:F ra

Etir f *? "$si :*H! e irlsSS !i.:: a : it:-S g{= = ? ':se d,ie P is= yse.vs* tS$ 9.F

ir-- . "*=-r- 7iz€t i$i E ikl < odE x\ -'.1l--E- Egd.;:: c1={ lGS t 3.3Z;Ee+s lii 8F

,?E - + ii$ = EF

069 e Fir I N)'=7- E i3 = eis 3 [$ F '?i:o'.:t:io

lmDo.lml Note : l. On compleLiig you eswqs, compul$rily dEs diagonal aos! lincs on rhe maining blMk pages,

I Any Ev€aling ol idenlif4alion, appeal lo evalualor od /or equations wrnLen eg. 42+8 = 50. wil be rreated as malprctice,

-z

o

;3

ge

Fpa:,

P,

{?.

=aq

"a:6

?3rod'/

iB*-a6€

9*

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{aa

ca

1* z =-t :: -! - -? I J{ z. =:^ ;i> : :,:6 5 rF: 6 ::@@=j

;+ss,gxs:sl E:;E i'gg;E5i;iiiEii=; seiiEEiE€iEaiigEig3: Ez € ;* i? E"iE""a aif,: EJq siiSB*'r;; -Eq{'ezarii ? fr 3 3; I +^ r aEEl *=l r'-5;E=; fi;rs*:B; ,3 : i r. 1E 6 E1=; st'e =;Ii?H E; 3;,qA*+ ; ; ? rs ia 3iF ai3==?jeE: B E E,iz E ; t c*E"f ; ;_E -E i_EEi[]=e; e- := A

-iC T i g i I= = ar a ;;. 6id e. q4 :. de;.'-- e e d -, 4a -'! =r_1 ; +e a1;sii ! 1 i;>i i + i a ?= * ; z-3 4caoe - 4

3ivoisuBs=igsi ;i ?yo ve"ys gs$E i.Ia:Eyp ss;'sy€s=l

$-;5Bg?5Fsi?aE, 3 $;3 E; ac Ea;r j ;iiii; ilEf?rr3*

ii r =5 cSoi - 4a 5 iB oiidi3 =-4i=e i- ;"i {tHii ;?F:"E E.: Erg a = Eq f,i i3i* a' E i= B E= ;7 35E€ r \g ^ ^^; 3i^- ," 1; Aaa i "

aad d-a e g aEe i ! PEd *=! ! i PFT Lr.= *i r 3 n

as!3

56 =6Ee

9.aq9 r'O>UO>>@ !] r=;-.lEaq : H! eLq F=g

5 =

e 6 i6;?4 s-zAitrdxf ::,:3 6 9:-6La =-

P-d ,=6 q 9a ;

e+'d5-

o3 E ,.:.

E,sE sE2. <O z A

a 9.5 ;1 i

a ''. "

E;e5'

2+

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l7

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E

EFtta+s

1j.i

{I g ; E? 2 Esi I 3I!:E : : >= = =;> > =>EE T E 8E g SgE g g€EaEE$

A = E)dt t ? o .!5; r', .') : !o; : E $ e !€4 J =>ai E *; EC E-E s :_E*":liB i eE:? E=H€ "*EiEg[''i;EEi E:sE= EE g ;E EE *; 5tg€ ss;=iEsE E5 E*11E91r 92.2 qaEcooi@'aB aa5 60 S 66 66 66 o-6E; a6€A6aaa 66u-Be : = E .= E;l E g i:E ; t z E a €i E 1 ;s r-e I ; : i E ; i ga : E 5 s< :: E

s€ E g E-! $= s,E € E ai oE : E :: ;:;E E j =,2 !E E! e s cE iE E E EE *

:g E : Ii TE€E B ! gE E; + E E;:E i ;:.lE iEiE :.E: =as i€ e r €q

*ffE;Egj,iE3E-',E ii*5*i,;i:FI=Ei 3i*=,u=5;sgiirg€= ,= ;i t ;E 8. ,= i t FE E= ,= :E t Ei

USN 06EI/IEL4t24

First/Second Semester B.E. Degree Examination, Jruune2Ol2

Elements of Mechanical EngineeringTime: 3 hrs. Max. Marks:10O

Note: 1. Answer FIVE full questions choosing at kast tv,o fr.om each part.L Answer all objective gtpe questions only on OMR sheet page 5 of the Answer Booklet.3. Answer to objective qpe questions on sheets other than OMR will not be valued.4. Use of steam tables is NOT permifred.5. Any missing data may be suitably assumed.

PART-A1 a. Choose your answers for the following :

I

3e8=;a7

Y!)

o'

99

E.<

-or

=q

AE

Ei

o{

oz

o.

iii) With increase in pressure, the enthalpy ofdry saturated steamA) increasesC) remains same

i) Fossil fuels areA) solid fuel B) liquid tuel

ii) The water tubes in Babcock-Wilcox boiler are inclined toA) Improve radiation heat transferC) Accommodate the furnace

(04 Marks)

C) gaseous fuel D) all of these.

B) Improve convective heat transferD) Promote natural convection of water

B) decreasesD) first increases and then decreases

(04 Marks)

D) Lawn sprhkler

B) diesel engine plantD) nuclear plant

iv) The specific volume of water, when heated at 0tA) first increases and then decreases B) first decreases and then increases

. C) increases steadily D) decreases steadily.b. List any four sources of energy, with suitable examples. (04 Marks)c' Describe with a neat sketch, the working of a Babcock-Wilcox boiler. Indicate clearly the(08 Marks)

i) it is wet with dryness fraction of 0.9ii) it is super heated with its temperature of 350oC.

[Take specific heat of super heated steam as 2.3 kllkgK and properties of steam at 20 bar ast,ut=212.4oC, hr= 908.6 kJ/kg, hr, = 1888.6 kJ/kgl (04Marks)

direclion of flow of flue gases.d. fina the enthalpy of 1.0 kg of steam al 20 bar when


i) . ........ turbine is an example of impulse turbine.

A) gas turbine plantC) steam turbine plant

A) De-Laval B) Kaplan C) Francisii) A gas turbine as compared to a diesel engine takes longer time to accelerate to full

speed becauseA) gas turbine has lesser maximum pressureB) diesel engine has larger number of bearingsC) gas turbine has larger rotating massD) gas turbine needs no water cooling.

iii) Kaplan turbine is efficient and preferred whenA) low head and low discharge is availableB) low head and high discharge is availableC) high head and low discharge is availableD) high head and high discharge is available.

iv) Cooling water is not needed in

I of 4

2b.

d.

3a.

b.c.

Classify water turbines.


i) The overall efficiency of an I.C. engine isA) mechanical efficiency B) brake thermal efficiencyC) indicated thermal efficiency D) none ofthese

ii) The air fuel ratio in a petrol engine is govemed by

B) 2: ID) none of these

With neat sketches, explain compounding of an impulse turbine.

06El.dEL4l24

(06 Marks)With a neat sketch, explain the construction and working of a closed cycle gas turbine plant.


(04 Marks)

A) iniectorC) carburetor

B) governorD) fly wheel

iii) The ratio of speed of the camshaft to speed of the crank shaft in a four stroke cycleengme ls

A) l:2C) 1:1

(06 Marks)

iv) For the same speed and power, the size of the flywheel of a four stroke petrol engine isA) iame as that of 2-stoke petrol engineB) larger than that of 2-stroke petrol engineC) smaller than that of 2-stroke petrol engineD) all of these.

Explain with a neat sketch, working ofa two stroke petrol engine.A single cylinder two stroke petrol engine develops 7.5 kW at 2500 rpm. The mean effectivepressure on the piston is 8 bar and mechanical efficiency is 807o. Calculate the diameter andstroke of the cylinder if stroke to bore ratio is 1.5. Also calculate the fuel consumption rate,if brake thermal efficiency is 287o. The calorific value of the fuel is 43900 kJ/kg. (10 Marks)


i) An ideal refrigerant should haveA) low fueezing pointC) high latent heat of vapourization

ii) In vapour-absorption refrigeration systemrefiigerantA) a pump and generatorC) both of (A) and (B)

b.

(04 Marks)

B) low boiling pointD) all of these.

is/are used to pressurize the

B) a compressorD) none of these.

(04 Marks)Indicate the state of the

(06 Marks)(06 Marks)d.

iii) Refrigeration is a process ofheat extraction fromA) a hot body and delivered to a cold body with the help of external workB) a cold body and delivered to a hot body without the help of extemal workC) a cold body and delivered to a hot body with the help of external workD) a hot body and delivered to a cold body without the help of external work.

iv) Air conditioning is a process ofA) control of temperature B) control of humidityC) control of cleanliness and air motion D) all of these.

Define : i) COP of refrigeration, ii) Ton of refrigeration.Draw a neat sketch of vapour compressor reftigeration system.refrigerant at all salient points and direction of flow of refrigerant.Describe room air conditioner with a simple sketch.

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06Ejs{814124

PART-B

5 a. Choose your answers for the following : (04 Marks)i) Which of the following parls is not present in lathe

A) spindle B) kneeC) bed D) slide

ii) Which of the following operations can be carried out on latheA) knurling B) facingC) thread cutting D) all of these

iiD...........istheoperationofenlargingaholebyasinglepointcuttingtool.A) reaming B) counter sinkingC) boring D) all of these

iv) Drilling machine can be specified based onA) max.dia. of drill B) spindle travelC) power of the motor D) all of these

b. With a neat sketch, explain taper turning on lathe by swiveling of compound slide. (06 Marks)c. Classify d{illing machines. (04 Marks)d. With neat sketches, explain : i) counter sinking, ii) counter boring, iii) reaming. (06 Marks)

6 a. Choose your answers for the following : (04 Marks)i) ........... is a machine tool that removes metal as the work is fed against a rotating

multipoint cutter.A) lathe B) drilling machineC) shaping machining D) milling machine.

ii) In a horizontal milling machine, the rotating spindle is called as

A) cutter B) yokeC) arbor D) over-arm

iii) Which of the following are natural abrasives. A) sand stone B) corundum

C) diamonds D) all of theseiv) . . . . . ... grinding produces flat surface.

A) cylindrical B) surfaceC) form D) none ofthese

b. Distinguish between up milling and down milling. (04 Marks)c. With a neat sketch, explain the working of vertical milling machine. (08 Marks)d. List the applications and advantages of centreless grinding. (04 Marks)

7 a. Choose your answers for the following : (04 Marks)i) Spot welding is an example of

A) gas welding B) resistance weldingC) TIG welding D) arc welding

ii) Which of the following can act as a lubricant?A) oil B) grease C) graphite D) all of these

iii) ........... is the property which enables oil to spread over and adhere to the surface ofbearing.

A) oiliness B) flash point C) specific gravity D) densityiv) Which of the following is demerit of ball bearing

A) less friction B) requires less lubricationC) compact D) none of these

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068I[.{E14t24

7 b. Distinguish between soldering, brazing and welding. (06 Marks)c. List the basic requirements of a good lubricant. (04 Marks)d. Describe with a neat sketch, working of a bushed bearing. (06 Marks)

I a. Choose your answers for the following : (04 Marks)i) Belt drives are preferred when the distance between the shaft centers is

A) very small B) largeC) any distance D) none ofthese

i, ......... gears connect two non-parallel, non-intersecting shafts which are usually atright angles.A) spur B) bevelC) worm D) none ofthese

iii) In a clock mechanism ....... Gear train is used to connect minute hand and hour hand.A) simple B) compoundC) epicyclic D) none of these

iv) Number of teeth on a wheel per unit of its pitch diameter is calledA) 'addendum B) deddendumC) diametral pitch D) circular pitch

b. Derive an expression for the length of the belt in a crossed flat belt drive. (06 Marks)c. Name different gear drives and mentiori their applications. (04 Marks)d. With neat sketches, explain : i) simple gear train, ii) compound gear train. (06 Marks)

4of4

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Basic Electrica! EngineeringTime: 3 hrs. Max. Marks: I OO

Note: 1. Answer any FIVE full questions, choosing at least two from each part.2. Answer all objective type questions only on OMR sheet page 5 of the answer booklet.3. Answer to objective gtpe qaestions on sheets othel than OMR will not be valued.

PART-A1 a. Choose your answers for the following :

i) The curent in 5 ohm resistor is

A) 2AB) 3Ac) lAD) 1.5A

ii) The'total resistance ofparallel circuit isA) less than the smallest resistance B) more than the smallest resistanceC) more than the highest resisrance D) none of these

iii) Inductance opposes _ in current in a chcuit.A) only increase B) only decrease C) change D) none ofthese

iv) If coefficient of coupling between two coils is increased, mutual inductance betweenthe coilsA) is increasedC) remains unchanged

List out advantages of parallel circuit over series circuit. List out characteristicscircuit.Deduce an expression for stored energy in a magnetic field.Find current in the battery, the current in each branch and p.d.shown in Fig.Ql(d).

First/Second Semester B.E. Degree Examination, June2Ol2

\ o-rr- Fig.Ql(a)(i)

B) is decreasedD) none of these (04 Marks)

of parallel(06 Marks)(04 Marks)

across AB in the network(06 Marks)

Fie.Ql(d)


i) A coil is rotating in the uniform field of a lO-pole generator. In one revolution of thecoil, the number of cycles generated by-voltage is _.A) t0 B)5 c) 2.5 D)4

D%

50v100 v40v140 V

ii) The average value of sine wave over a one complete cycle is

A) zero B) +l c) -liii) The voltage of the applied source in the circuit of fig.Q2(aXiii) is

Q2(a)(iii)

A)B)c)D)

1of 4

2a iv) The power taken by the circuit shown is

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A) 480 WB) 1920Wc) 1200wD) none of these (04 Marks)

l-? 3a S>Fig.Q2(aXiv)

b. With the help of circuit diagram and phasor diagram, find the phase angle, impedance andpower in case of R-L series circuit. (08 Marks)

c. An altemating current of frequency 60 Hz has a maximum value of 120 A.i) Write down equation for the instantaneous value.ii) Reckoning time from the instant the current is zero and becoming positive, find the

instantaneous value after 1/360 sec.

iii) Time taken to reach 96 A for the frst time. (04 Marks)

A 60 O resistor is connected in parallel with an inductive reactance of 80 Q to a 240 Y,50 Hz supply. Calculate: i) The current through the resistor and inductance, ii) The supplycurrent, iii) The circuit phase angle. Draw phasor diagram. (04 Marks)


i) Three inductive coils each having an impedance of 17.7 {2 are connected in star. Thecircirit is fed from a 3-phase, 400 V,50 Hz supply. The current (line) drawn by thecircuit is equal toA) 22.6 A B) 39.14 A D) none of these

ii) For a 3-phase star connected balanced circuit having inductive load, the angle betweenthe line currents and corresponding line voltages is equal toA) 30" B)30"-0 C)30"+g D)0

iiD When two wattmeters are connected in a 3-phase circuit to measure its total powerconsumption, one ofthe wattmeter would read zero, when the load power factor is,A) 0.2 lagging B) unity C) 0.5 lagging D) zero

iv) Active power drawn by a 3-phase balanced load is given by

3a.

b. With the aid of a phasor diagram obtain the relationship between the line and phase valuesof voltages in a three-phase, star connected system. (08 Marks)

c. The three arms of a three-phase load each comprise an inductor of resistance 25 Q and ofinductance 0.15 H in series with a 120 prF capacitor. The supply voltage is 415 V, 50 Hz.Calculate the line current and total power in watts, when the three arms are comected indelta. (0E Marks)


i) The type of wattmeter commonly used for measurement of power in ac circuit is

c)13A

B) P = J'VLILD) P = 'r[Vr1lo5 cos $

A)P=V1I1cos$C) P = JiVrI,- cos 0

A) rectifier typeC) moving iron tlpe

A) shunt magnetC) braking magnet

(04 Marks)

ii) In energy meter, constant speed of rotation of disc is provided by

B) dynamometer typeD) thermo-couple tlpe

B) series magnetD) none of these

B) personnel against electric shockD) all of these

B) duration of currentD) all of these

iii) Earthing of electrical installation is carried out to protectA) equipments from damageC) equipments from shon circuit

iv) The effect of electric current on vital human organs depends uponA) magnitude of currentC) frequency of current

2of4(04 Marks)

4b.1OELE15i25

With a neat sketch, explain the construction and principle of operation of single phaseinduction type energy meter. (08 Marks)Name different types of domestic wiring and explain any one t)?e of wiring. (05 Marks)List out some safety measures against electric shocks. (03 Marks)

PART-BChoose your answers for the following :

i) The rotating part of d.c. machine is called _.A) armature B) field system C) frame D) yoke

ii) E.M.F. of d.c. machine s inversely proportional to

5a.

c.d.

b.

c.d.

A) flux/poleC) conductors

iii) Torque in d.c. motor is proportional toA) only fluxC) both flux and Iu

B) polesD) number of parallel paths

B) only I^D) none of these

iv) At the moment of starling a d.c. motor, its back emf isA) zero B) maximum C) minimum

Derive e.rir.f. equation of a d.c. generator.Explain the principle of torque production in d.c. motor.

6a.

b.


i) The frequency of voltage generated by an alternator250 rpm is

An 8-pole, lap-connected armature has 40 slots with 12 conductors per slot, generates avoltage of 500 V. Determine the speed at which it is running if the flux per pole is 50 mwb.

(06 Marks)


i) Which of the following does not change in an ordinary transformer?A) voltage B) current C) frequency D) all of these

ii) A transformer has full load copper loss of 800 W and core loss of 600 W. Total loss atno load will be approximately.A) 1400Wans B) I 100 Watts C) 1000 Watts D) 600 Watts

iii) The efficiency of a transformer at fuel load 0.8 pf lag is 95Vo.The efficiency at 0.8 pflead is

4t) 99Vo B) 95.5Vo C) 959o D) 90Voiv) A single phase transformer has 250 tums on primary and 1000 tums on the secondary

winding. If the primary winding is connected across a 230 y , 50 Hz, single phasesupply, the voltage induced in the secondary winding isA) 920 V B) 230 v C) 1840 V D) 690 V (04 Marks)

Explain briefly the principle of operation of transformer and show that the voltage ratio ofthe primary and secondary winding is the same as their tums ratio. (08 Marks)A transformer is rated at 100 KVA. At full load its copper loss is 1200 W and its iron loss is960 W. Calculate:D The efficiency at full load, unity power factori, The efficiency at halfload,0.8 p.f.iii) The load KVA at which maximum efficiency will occuriv) Maximum efficiency at 0.85 p.f.

D) optimum(04 Marks)(06 Marks)(04 Marks)

(08 Marks)

having 8-poles and rotating at

Drc!HzA) 60 Hz B) 50 Hz

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C) 25 Hz

7a. ii) In modem altemators, the rotating part isA) fieldC) field and armature

A) RBYC) YRB

A) equal to full load currentC) more than l0 times

lOELEtsl25

B) armatureD) none of these

B) RYBD) none of these

C) I D) infinityslip, then the actual running speed of an

C) (l -s)Ns D) (Ns- l)s

B) 2 timesD) 5 times (appx) (04 Marks)

(06 Marks)

iii) An alternator has a phase sequence of RYB for its phase voltage. In case the directionof rotation of alternator is reversed, the phase sequence will become

8a.

b.

c.d.

c.d.

iv) Alternators have short-pitched winding so as toA) increase machine rating B) improve the voltage waveformC) improve generated voltage D) none ofthese (04 Marks)

Explain the essential difference between cylindrical and salient pole rotors. (04 Marks)Derive e.m.f equation of an alternator. (06 Marks)A 3-phase, 6-pole, star connected alternator revolves at 1000 rpm. The stator has 90 slotsand 8 conductors per slot. The flux per pole is 0.05 wb. Calculate voltage generated, ifKw = 0.96. (06 Marks)


i) The.speed at which the rotating magnetic field produced by stator currents rotates isA) synchronous speed B) rotor speedC) greater than synchronous speed D) none of these

ii) When an induction motor is at standstill its slip isA) zero B) 0.5

iiD If Ns is synchronous speed and 's' is theinduction motor will be

A)Ns B) sNsiv) Initial starting current drawn by a 3-phase induction motor in terms of full load current

on application of rated voltage (approximately) is:

b. Explain the principle of operation ofa 3-phase induction motor.Deduce an expression for the frequency ofrotor current in an induction motor. (04 Marks)A 3-phase, 6-pole, 50 Hz induction motor has a slip of l7o at to load, and 3olo at full load.Determine: i) slmchronous speed, ii) no-load speed, iii) full load speed, iv) frequency ofrotor at stand still, v) frequency ofrotor current at full load. (06 Marks)

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4 of4

USN 06ELEL5l25

B) AluminiumD) Silicon carbide

B) Right hand thumb ruleD) Lenz's law

B)mD) None of these

B) L"q = L1 +Lz+2MD)L"q=2L1 +L2-M

D) 45"

D) 0.63sseries circuit is increased the

(05 Marks)f) and an inductance of 0.05 H connected in series.

the circuit. Find the current, power factor and power(05 Marts)

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First/Second Semester B.E. Degree Examination, June 2012Basic Electrical Engineering

Time: 3 hrs. Max. Marks: lO0

Note: 1. Answer any FIVE full questions, choosing at least two from each part.2. Answer all objective type questions only on OMR sheet page 5 of the answer booklet.3. Answer to objective Epe questions on sheets other than OMR will not be valued.

PART - AI a. Choose your answers for the following :

i) Ohm's law does not hold good for non-metallic conductors such as

(04 Ma*s)

iD The direction of magnetic field produced by a linear cunent is given by _

A) CopperC) Silver

A) Ilemings left hand ruleC) Amper's law

A)1C) zero

A) L"q = Lr +L2-214C) L"q = Ly +2L2+M

iiD For ideal voltage source, the value ofintemal resistance is

iv) Equivalent inductance of series aiding of two coil connection is

c.

d.

2a.

b. A resistance R is connected in series with a parallel circuit comprising two resistances ofl2 Q and 8C). The total power dissipated in the circuit is 700 watts when the applied voltageis 200V. Calculate the value of R. (06 Marks)State and explain Faraday's law of electromagnetic induction and state Lenz's law also.

(05 Marks)Two coupled coils of self inductances 0.8 H and 0.20 H, have a co-efficient of coupling 0.9.Find the mutual inductance and turns ratio. (05 Marks)

Choose your answers for the following : (04 Marks)i) The sinusoidal currents are given by ir = l0 Sin (wt + fl/3), iz = 15 Sin (wt - n/4). The

phase difference between them in degrees is

b.

A) l5o B) 105' c) 60"ii) The peak factor is given by Kp = _

A) 1.414 B) I .t r C) 0.707iii) When the fiequency of the applied voltage in R.L

voltage, cuuent and power.A circuit consists of a resistance of 20A supply of 230V, 50Hz is applied toconsumed by the circuit.

inductive reactanceA) decreases B) becomes zero C) increases D) remains same

D) zeroiv) The power factor of R.L.C. series circuit, when Xr > Xc

A) lagging B) leading C) unityDerive equations for the rms value and average value ofa sinusoidally varying cument.

(06 Marks)Derive an equation for the power consumed by a R-C series circuit. Draw the waveforms of

06ELE1s/2s

3 a. Choose your answers for the following : (04 Marks)i) The algebric sum of instantaneous phase currents on a three phase balanced system is

A) one B) zeroC) infinity D) none of these

ii) In star connected system, the relation between the line voltage and phase voltage is

A) E/=Eph B)Eph= 16EiC)E/=rEEph D)E/=3Eph

iii) In the two-wattmeter method of measuring 3-phase power, one of the wattmeter readszero, when the load angle power factor angle isA) 60" B)ooc) 90" D) 30"

iv) The expression of 3.$ power equation in terms of phase values

A) 3 Vph Ipn Sin $ B) rE Vpr, Ipr, Cos $

C) 3 Vpt, Ipr., Cos O D) ,,'.6 Von Ion Sin O

b. With rehvant vector diagram, show that two wattmeters are sufficient to measurethree-phase power. (08 Marts)

c. Thrce equal impedances, each having a resistance of 8O and inductive reactance of 6O areconnected in i) Star; ii) Delta, across a 3-phase,440V supplyFind :

i) Phase currentiD Line currentiii) Total power consumed by the circuit in both cases. (08 Marfts)

4 a. Choose your answers for the following : (04 Marks)i) The number of revolution of the disc in energy meter is directly proportional to the

consumedA) powerC) voltage

ii) Integrating meters are used for the measurement ofA) currentC) power

A) potential coilC) curent or potential coil

A) mediumC) low

c. With a neat diagram explain plate earthing.d. Define the following terms with reference to fuses :

i) Rated currentiD Fusing currentiiD Fusing factor.

iii) In a dynamometer wattmeter, the moving coil is _

B) energyD) current

B) voltageD) energy

B) cunent coilD) none of these

B) highD) none of these

iv) A good earthing should provide _ resistance in earthing path

b. Explain with a neat diagram the working of dynamometer type wattmeter. (08 Marks)(04 Marks)

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(04 Marks)

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Physics Stream (2012-July) Question Papers