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    Disclaimer :

    The questions have been shared by students only. Since the questions are

    purely memory based, , does not take any responsibilityregarding the correctness of questions.

    In case there is any kind of discrepancy in questions please write to us at

    or call us at :

    IES Master

    [email protected] Ph: 011-41013406, 09711853908

    for rectification/deletion/updation of the same.

    (Evening Session)

    16 t h F e b ru a r y, 2 0 14

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    1. The value of the integral :

    2 2

    20

    sin1 1d

    cos1 1

    x x xx x

    is

    (a) 3 (b) 0

    (c) 1 (d) 2

    Sol. : (b)

    I =

    22

    20

    1 sin 1

    1 cos 1

    x x

    x xdx

    =

    22

    20

    2 1 sin 2 1

    2 1 cos 2 1

    x x

    x x

    =

    22

    20

    1 sin 1d

    1 cos 1

    x xx

    x x

    =

    22

    20

    1 sin 1d

    1 cos 1

    x xx

    x x

    I = I

    I = 0

    2. Match Group A with Group B :

    Group A Group B

    P. Biot number 1. Ratio of buoyancy to viscous force here

    Q. Grashof number 2. Ratio of inertia force to viscous force

    R. Pranolt number 3. Ratio of momentum to thermal diffusivity

    S. Reynolds number 4. Ratio of internal thermal resistance to

    boundary layer thermal resistance

    (a) P4, Q1, R3, S2 (b) P4, Q3, R1, S2

    (c) P3, Q2, R1, S4 (d) P2, Q1, R3, S4

    Sol. : (a)

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    3. The total number of decision variables in the objective function of an assignment problem of size n

    n (n jobs and n machines) is

    (a) n2 (b) 2n

    (c) 2n 1 (d) n

    Sol. : (d)

    The total no. of decision variables in the objective functions of an assignment problem of size

    n n is n.

    4. Within the heat affected zone (HAZ) in a fusion welding present the work material undergoes

    (a) micro structure changes but doesnt melt

    (b) Neither melting and micro structure changes

    (c) both melting and micro structure changes

    (d) melting and retaining the original microstructure after solidification

    Sol. : (a)

    The area of base metal adjacent to the weld pool is called heat affected zone. Since this area is

    subjected to a high temperature for considerable period of time as compared to the rest portion

    of base metal, its microstructure changes and different from base metal prior to welding.

    5. A f low field which has only convective acceleration is

    (a) a steady uniform flow (b) an unsteady uniform flow

    (c) a steady non-uniform flow (d) an unsteady non-uniform flow

    Sol. : (c)

    In case of steady flow local acceleration = 0

    In case of uniform flow convective acceleration = 0

    In case of steady uniform flow, all accelerations are zero

    Hence convective acceleration exists only for steady non-uniform flow.

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    Office Address : F-126, Katwaria Sarai, New Delhi - 110 016.Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406

    Web : www.iesmaster.org E-mail : [email protected]

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    8. Demand during lead time with assumed probabilities is shown below :

    Demand 50 70 75 80 85

    Probability 0.15 0.14 0.20 0.30 0.30

    Expected demand during lead time is .......

    Sol. :

    Excepted demand during lead time

    = 50 0.15 + 70 0.14 + 75 0.20

    = 81.8

    9. Moist air at 35C and 100% relative humidity is entering a psychrometric device and leaving at 25C

    and 100%, relative humidity. The name of the device is

    (a) Humdifier (b) Dehumidifier

    (c) Sensible heater (d) Sensible cooler

    Sol. : (b)

    Moist air at 35C and 100% RH

    25C, 100% RH

    Name of device is

    At 35C W1

    At 25C W2

    w1w2

    W1 > W

    2

    Dehumidifier (b)

    10. Two separate slab milling operation 1 and 2 are performed with identical milling cutter the depth of

    cut in operation 2 is twice that in operation 1. The other cutting parameters are identical. The ratio

    of maximum uncut chip thickness in operation 1 and 2 as .....

    Sol. : 0.5

    1 1 1

    2 2 1

    t d d0.5

    t d 2d

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    Office Address : F-126, Katwaria Sarai, New Delhi - 110 016.

    Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406Web : www.iesmaster.org E-mail : [email protected]

    11. If the Poissons ratio of an elastic material is 0.4, the ratio of modulus of ridigity to youngs modulus

    is.....

    Sol. : Modulus of rigidity

    G =

    E

    2 1

    G

    E=

    1

    2 1 =

    1 1

    2 2.81.4 = 0.357

    12. Laplase transform of cos t is 2 2s

    s . The Laplase transform of 2te cos(4t)

    is

    (a) 2s 2

    16s 2

    (b) 2

    s 2

    16s 2

    (c) 2s 2

    16s 2

    (d) 2

    s 2

    16s 2

    Sol. : (d)

    L[cos t ] = 2 2s

    s

    L[cos 4t] = 2s

    s 16

    L[2te cos4t ] = 2

    s 2

    (s 2) 16

    13. Which one of the following is used to convert a rotational motion into a translational motion

    (a) Bend gears (b) Double helical gears

    (c) Worm gears (d) Rack and pinion gears

    Sol. : (d)

    Rotational - Translational

    Rack and Pinioin

    Rack

    Pinion

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    Office Address : F-126, Katwaria Sarai, New Delhi - 110 016.

    Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406Web : www.iesmaster.org E-mail : [email protected]

    Sol. : (d)

    (a) P (Q + R) = PQ + PR

    So a is incorrect

    (b) (P Q)2= (P Q) ( P Q)

    = P2 PQ QP Q2

    = P2PQ QP Q2

    So (b) is incorrect

    (c) | P + Q | = | P | + | Q |

    It is not true

    (d) (P + Q)2= (P + Q) (P + Q)

    = P2 + PQ + QP + Q2

    So (d) is correct

    18. In a rolling process the maximum possible draft, defined as the difference between the initial to the

    final thickness of the metal sheet, mainly depends on which pair of the following parameters ? P-

    strain, Q - Strength of the work material R - Roll diameter, S - Rolls velocity, T - coefficient of friction

    between roll and work

    (a) Q, S (b) R, T

    (c) S, T (d) P, R

    Sol. : (b)

    We know that maximum draft in rolling is given by

    (h)max

    2R

    or

    (h)max

    = 2R

    where,

    : coefficient of friction between roll and work piece

    R : Radius of roll.

    Hence option (b) is correct.

    19. A Carnot cycle refrigerator maintaining a temp of 5C the ambient air temp is 35C. The heat gained

    by refrigerator at a continuous rate is 2.5 kJ/s. The power/ in watts required to pump this heat out

    continuously is ...

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    Sol. :

    carnotCOP =2

    1 2

    T

    T T

    =273 5

    35 5

    = 6.7

    6.7 =absorbQCOPW

    6.7 =2.5

    kJ sW

    W

    2.5 KJ/s

    T25C

    Qrelease

    Qabsorb

    W =2.5

    0.3731 KJ s6.7

    20. Ball bearings are rated by manufacturer for a life of 106revolution. The catalouge rating of particular

    bearing is 16 kN. If the design load is 2 kN, the life of the bearing will be P 106revolution, where

    P is equal to ....

    Sol. :

    106revolution

    Catalogue rating of bearing = 16 KN

    Design Load = 2 KN

    Life = P 106revolution

    L10

    =

    3C

    P

    life in million revolution

    C = 16 kN

    P = 2 kN

    L10 =3

    16512

    2

    LIfe in million hours

    So P = 512

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    Office Address : F-126, Katwaria Sarai, New Delhi - 110 016.

    Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406Web : www.iesmaster.org E-mail : [email protected]

    21. The no. of independent elastic constant required to define the stress- strain relationship for an

    isotropic elastic solid is ...

    Sol. : Two

    22. The principle of material removal in electrochemical machining is

    (a) Ficks laws (b) Faradays laws

    (c) kirchhoffs Laws (d) Other Laws

    Sol. : (b)

    Material removal in electrochemical machining is based upon Faradays law.

    23. As the temp. increases, the thermal conductivity of gas

    (a) increases (b) decreases

    (c) remain constant (d) increase up to certain temp. and then decreases.

    Sol. : (a)

    In case of gases as the temperature increases the intra-molecular collisions increases which are

    sole responsible for heat conduction in gases. So the conductivity of gases increases with increase

    in temperature.

    Hence option (a) is correct.

    24. Kaplan water turbine is commonly used when the flow through its runner is

    (a) axial and the head available is more than 100 m

    (b) axial and the head available is less than 10 m

    (c) radial and the head available on more than 100 m

    (d) mixed and the head available is about 50 m.

    Sol. : (b)

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    25. Match the heat treatment process (Group A) and their associated effects on properties (Group B)

    of medium carbon steel

    Group - A Group - B

    P - Tempering 1. Strengthening and grain refinement

    Q - Quenching 2. Increasing toughness

    P - Annealing 3. Hardening

    S - Normalising 4. Softening

    (a) P - 3, Q - 4, R - 2, S - 1

    (b) P - 2, Q - 3, R - 4, S - 1

    (c) P - 3, Q - 2, R - 4, S - 1

    (d) P - 2, Q - 3 , R - 1, S - 4

    Sol. : (b)

    26. Steam with specific enthalpy (h) 3214 kJ/kg enters an adiabatic turbine operating at steady statewith, flow rate 10 kg/s. As it expands, at a point where h is 2920 kJ/kg, 1.5 kg/s enteracted for

    heating purpose the remaining 8.5 kg/s further expands to the turbine exit, where h = 2374 kJ/kg

    neglecting changes is kinetic and potential energies, the net power output (in kw) of the turbine is

    2 marks

    Sol. : (c)

    h1

    = 3214 KJ/kg

    m = 10 kg/s

    h2

    = 2920 KJ/kg

    m1

    = 8.5 Kg/s

    h3

    = 2374 KJ/kg.

    KE = 0; PE 0

    work output = 1 2 31 2m m h hh h

    = 10 8.53214 2920 2920 2374

    = 7581 KJ/s = 7581 KW

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    Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406Web : www.iesmaster.org E-mail : [email protected]

    27. The value of the integral2 x

    x y

    0 0

    e dydx is

    (a)1

    (e 1)2

    (b) 1/2 (e2 1)2

    (c) 1/2 (e2 e) (d) 1/2 (e - 1/e)2

    Sol. : (b)

    2y

    0 0

    e dy d x

    x x =

    2y

    0

    0

    e e d x

    x x

    =

    2

    0

    e e 1 d x x x

    = 2

    2

    0

    e e d x x x

    =

    22

    0

    1e e

    2

    x x

    =4 21 1e e e e

    2 2

    =4 21 1e e

    2 2

    = 4 21

    e 2e 12

    = 2

    21 e 12

    28. A flame is subjected to a load P as shown. The frame has a constant flexural rigidity EI. The effect

    of air at load is negleted. The deflection at point A due to the applied load P is

    L

    L

    A

    P

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    (a)31 PL

    3 EI(b)

    32 PL

    3 EI

    (c)3PL

    EI(d)

    34 PL

    3 EI

    Sol. : (d)

    A

    PL, EI

    L, EI

    Total deflection at A = 1 2

    PL

    P

    PL

    P P

    L

    1= L

    1

    (PL)LL

    EI

    =

    3PL

    EI

    P

    2 =PL

    3EI

    3

    Total deflection 1 2 =34PL

    3EI

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    Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406Web : www.iesmaster.org E-mail : [email protected]

    29. A cylindrical riser of a 6 cm diameter and 6 cm height has to be designed for a sand casting mould

    for producing a steel rectangular plate casting of 7 cm 10 cm 2 cm dimention having the total

    solidification time of 1.36 minute. The total solidification time (in minutes) of riser is .......

    Sol. : (c)

    Solidification time of casting

    tc =

    2

    VKA

    1.36 =

    27 10 2

    K2(7 10 10 2 2 7

    =

    2140

    K208

    1.36 =

    235

    K52

    (i)

    Solidification time for riser,

    tR

    =

    2V

    KA

    =

    2d

    K6

    tR

    =

    26

    K6

    (ii)

    From eq. (i) and (ii)

    tR =2

    1.3635

    52

    = 3.00

    Rt 3.00 min

    30. A wardrobe (mass 100 kg, height - 4m, width 2m, depth 1m) symmetric about the Y Y axis

    stands on, rough level floor as shown in fig. A force P in applied at mid height on the wardrobe so

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    as to toppling about point Q without slipping, what are the minimum values of the force (in newton)

    and the static coefficient of friction between the floor and the wardrobe respectively ?

    P

    Qy

    y

    (a) 490.5 & 0.5 (b) 98.1 & 0.5

    (c) 1000.5 & 0.15 (d) 1000.5 & 0.25

    Sol. : (a)

    P4

    Q

    1

    Toppling about point Q; P = ? without slippingFBD

    Taking Toruqe about 0

    4P

    2 = mg 1

    P =100 9.81 1

    2

    = 490.5 N

    N = P

    P

    N

    mg

    N =

    P P 490.50.5

    N Mg 100 9.81

    31. At a work station, 5 jobs arrive every minute. The mean time spent on each job in the work-station

    is 1/8 minute. The mean steady state no. of jobs in the system is ____________.

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    Telephone : 011-41013406, Mobile : 8130909220, 9711853908, 7838813406Web : www.iesmaster.org E-mail : [email protected]

    Sol. :

    Arial Rate, = 5 job minute

    = 7.5 Job/min [ ]

    No. of Jobs in the system =

    50.6667.5 2

    51 1 0.6661

    7.5

    32. A GO NO GO plug gauge is to be designed for measuring a hole of nominal diameter 25 mm with

    a hole tolerance of 0.015 mm. Considering 10 % of work tolerance to be the gauge tolerance and

    no wear condition the dimension (in mm) of the GO plug gauge as per the unilateral tolerance system

    is ______________.

    (a)0.0030.00324.985

    (b)

    0.0000.00625.015

    (c)0.030.0324.985

    (d)

    0.0030.00024.985

    Sol. : (d)

    Hole size = 25 0.015 mm

    Hole

    Work tolerance zone

    25mm

    LL

    Zero line

    Datum line

    UL

    Upper limit of hole,

    UL = 25.015 mm

    Lower limit of hole, LL = 24.985 mm

    Work tolerance = UL LL = 0.03 mm

    Gauge tolerance = 10% of work tolerance

    = 0.1 0.03

    = 0.003 mm

    For number wear condition size of GO gauge

    = LL of hole + Gauge tolerance

    = 24.985 + 0.003

    = 24.988 mm

    As per unilateral system, it can be written as + 0.003

    24.985 0.000 mm

    Hence option (d) is correct.

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    33. Torque and angular speed data over one cycle for a shaft carrying a flywheel as shown in the fig.

    The moment of inertia (in kg.m2) of the flywheel is _______________.

    Torque

    3000

    N-m

    3/2 2/20

    1500

    N-m

    Angular speed

    20 rad/s

    3/2 2/20

    10 rad/s

    Sol. :

    E =2

    sI C

    = max min20 0

    10= =2 2

    CS

    = max min20 0

    2= =10

    E = 3000 1500 22

    = 3000

    3000 = 2I 10

    I = 47.1238 Kg m2

    34. A single degree of freedom system has a mass of 2 kg. Stiffness 8 N/m and viscous damping ratio

    of 0.02. The dynamic magnification factor at an excitation frequency of 1.5 rad/s is __________.

    Sol. : Single degree of freedom m= 2 kg

    K = 8 N/m; = 0.02; Wn = K m 2rad s

    W = 1.5 rad/s

    Dynamic Magnification Factor =2 22

    nn

    1

    ww21

    ww

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    =2 22

    12.28

    1.51.52 0.021

    22

    35. Two identical metal blocks L & M (specific heat : 0.4 kJ/kg-K), each having a mass of 5 kg, are

    initially at 313 K. A reversible refrigerator extract heat from block L and rejects heat to block M until

    the temp. of block L reaches 293 K. The final temp. (in K) of block M is _____________.

    Sol. : (c)

    LS = MC ln LfT

    313 ... (1)

    mS = MC lmmfT

    313 ...(2)

    universe( S) 0

    But since the system is reversible

    L mS S = 0

    MC lnf mf

    2

    T T

    (313)

    l= 0

    ln

    f mf

    2

    T T

    (313)

    l=l

    n1

    f mf

    2

    T T

    (313)

    l= 1

    Tmf

    =

    2

    f

    (313)

    T

    l

    Tmf

    = 334.36 K

    36. The precedence relation and duration (in days) of activity of a project network are given in the table.

    The total float (in days) of activities e & f, respectively, areActivity Predecessors Duration (days)

    a 2

    b 4

    c a 2

    d b 3

    e c 2

    f c 4

    g d, e 5

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    (a) 0 & 4 (b) 1 & 4

    (c) 2 & 3 (d) 3 & 1

    Sol. : (b)

    a

    b

    d

    34, 4

    4

    2

    7, 7g

    5

    12, 12

    4

    e

    f

    c4, 52, 3

    0, 02

    2

    For activity C FT= (7 4) 2 = 1

    For activity f FT= (12 4) 4 = 4

    37. A ladder AB of a length 5 m & weight (w) 600 N is resting against a wall. Assuming frictionless

    contact at the floor (B) and wall (A), the magnitude of the force P(in newton) required to maintain

    equilibrium of the ladder is _________.

    w

    2.5m

    2.5m3 m

    B

    A

    4 m

    P

    Sol. :

    w

    2.5m

    2.5m3 m

    B

    A

    4 m

    P

    N2

    N1

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    Since here is frictionless contact at A and B reactionless contact at A and B will be rto thesurface

    W = 600N; P = ?

    Thus, for frictionless wall and floor

    W = N2

    N1

    = P

    Taking torque about A.

    W 2.5 cos + P 3 = N2 4

    4

    W 2.5 3P5

    = W 4 (cos = 4/5)

    2W = 3P

    P =2W 2 600

    3 3

    = 400 N

    38. Water flows through a tube of diameter 25 mm at a an average velocity of 1.0 m/s. The properties

    of water are P = 1000 kg/m3, = 7.25 104N-S/m2, K = 0.62 W/mK, Pr = 4.85. Using Nu =0.023 Re0.8Pr0.4, the connective heat transfer coefficient (in W/m2K) is __________.

    Sol. : d = 0.025 m

    V = 1 m/s

    P = 1000 kg/m3

    = 7.25 104N-S/m2

    K = 0.62 W/mK

    Pr = 4.85

    Re = 4PVd 1000 1 0.025

    7.25 10

    = 3.448 104

    Nu = 0.023 Re0.8Pr0.4

    hD

    K= 0.023(34482.7586)0.8(4.85)0.4

    hD

    K= 184.5466

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    h =184.5466 0.62

    0.025

    = 4567.7566 W/m2K

    / 2h 4567.7566 W m K

    39. If Z in a complex variable, the value of3i

    5

    dz

    z is _____________.

    (a) 0.511 1.57 i (b) 0.511 + 1.57 i

    (c) 0.511 1.57 i (d) 0.511 + 1.57 i

    Sol. : (b)

    3

    5

    dz

    zi

    = 3

    5logz i

    = log3i log 5

    = 2 2 11 3

    log 0 3 i tan log52 0

    = log 3 + i log52

    =3

    log 1.575

    i

    = 0.511 + 1.57i

    40. Two infinite long parallel plates are placed at a certain distance apart. An infinite long radiation shield

    is inserted between the plates without touching any of them to reduce heat exchange between the

    plates. Assume that the emmisivities of plates and radiation shield are equal, the ratio of the net

    heat exchange between between the plates with and without the shield is

    (a) 1/2 (b) 1/3

    (c) 1/4 (d) 1/8

    Sol. : (a)

    For same emmisivity of plates,

    qwith shield

    =

    without shieldq

    n 1

    where n= number of shield inserted.

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    Here, n= 1

    q

    q

    withshield

    withoutshield

    1

    2

    Hence option (a) is correct.

    41. Consider the following statement regarding streamline (s)

    I. It is a continuous line line such that the tangent at any point on it shows the velocity vector at

    that point.

    II. This is no flow across streamlines

    III.du dy dz

    u v w is the differential equation of sreamline where u, v and w are velocities in direction

    x, y and z respectively.

    IV. In an unsteady flow, the path of a particle is a streakline.

    (a) I, II, IV (b) II, III, IV

    (c) I, III, IV (d) I, II, III

    Sol. : (a)

    Statement (iii) is wrong because for stream linedx

    u=

    dy dz=

    In an unsteady flow, ends points of Particle path is on a streak line

    42. In a compression ignition engine, the inlet air pressure is 1 bar and the pressure at the end of

    isentropic compression is 32.42 bar. The expansion ratio is 8. Assuming ratio fo specific () is 1.4the air standard efficiency (in percent) is ..........

    Sol. :

    r = 1 1.4 11.99932.42

    =r 11 999

    1 4998= =8.

    .

    =1

    11 11

    1r r

    =

    0 4 1 41 1 11 499811 4 12 1 4998 1

    . ..

    . .

    = 0.5959

    = 59.5938%

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    43. A thin gas cylinder with an internal radius of 100 mm is subject to an internal presure of 10 MPa,

    the max permissible working stress is restricted to 100 MPa. The minimum cylinder wall thickness

    (in mm) for safe design must be ....

    Sol. :

    d = 100 mm

    t = ?

    p = 10MPa

    Max stress =pd

    2t p

    d

    t

    for safetypd

    2t

    tpd

    2

    t10MPa 200

    mm2 100 MPa

    t 10 mm

    tminShould be 10 mm

    44. A cast iron block of 200 mm length in being shaped in a shaping machine with a depth of cut of

    4 mm, feed of 0.25 mm/stroke and the tool principal cutting edge angle of 30. No of cutting strokes

    per minute in 60. Using specific energy for cutting as 1.49 J/mm3the average power consumption

    in watt is ...................................

    Sol. : Given a cost iron block.

    d

    L

    Direction of

    cutting strokeLength, L = 200 mm

    Depth of cut, d = 4 mm

    Feed, f = 0.25 mm/stroke

    Number of strokes = 60 / min = 1 / sec.

    Material removal rate (MRR) = L d f No. of stroke/sec

    = 200 4 0.25 1

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    = 200 mm3/s

    Average power consumption (P) = Specific energy MRR

    P = 1.49 200 = 298 J/s

    P 298 watt

    45. A plane wall has a thermal conductivity of 1.15 w/m k// If the inner surface is at 1100C and the outer

    surface is at 350C, then the design thickness in meter of the wall to maintain a steady heat flux

    of 2500 w/m2should be

    Sol. : Given,

    k = 1.15 w/mk

    T1

    = 1100C

    T2

    = 350C

    T2

    T1

    b

    q

    b : Thickness of the wall

    q = 2500 w/m2

    q = Tkb

    2500 =

    1100 350

    1.15b

    b = 0.345 m

    b 34.5 cm

    46. A bolt of major diameter 12 mm is required to clamp two steel plates. Cross sectional area of the

    threaded portion of the blot is 84.3 mm2. The length of the threaded portion in grip is 30 mm, while

    the length of the unthreaded portion in grip is 8 mm young modulus of material is 200 GPa the

    effective stiffness (in Nm/m ) of the bolt in the clamped zone in

    Sol. :

    d1

    = 12m

    1 = 8mm A

    1 =

    2 2

    1/4d 110.09 mm=

    A2

    = 84.33 mm2

    2 = 30mm

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    P ( x < 2) = P(x = 0) + P (x = 2)

    = 5.2 5.2e 5.2 e 5.2

    0.1 1.1

    = 5.2e (1 5.2)

    = 0.034

    49. A shaft is subjected to pure torsional moment. The maximum shear stress developed in the shaft

    is 100 MPa. The yield and ultimate strength of the shaft material in tension are 300 MPa and 450

    MPa respectively. The factor of safety using maximum distortion energy (Von-mises) theory is

    Sol. :

    Max Shear stress =T

    J

    max shear stress =4 3

    T D/2 16T100MPa= =

    D D

    32

    As per max distortion energy theorem

    T

    1 =

    2 =

    3 = 0

    2 2 2

    2 3 3 11 2

    1

    2

    2fy

    F.O.S

    2 221

    22

    2fy

    F.O.S

    26

    2

    2fy

    F.O.S

    F.O.S2 2

    2 2

    2fy fy=

    6 3

    F.O.S =fy / 3 300

    3= =3 100

    F.O.S. = 1.732

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    50. A closed system contain 10 kg of saturated liquid ammonia at 10C. Heat addition required to convert

    the entire liquid into saturated vapour at a constant pressure is 16.2 MJ. If the entropy of the

    saturated liquid is 0.8 deg. kJ/kg K the entropy (in kJ/kg K) of saturated vapour is

    Sol. :

    m = 10 kg, T = 10C satinated ammonia

    Q = 16.2 MJ to connect liquid into saturated vapour at constant pressure

    Sl = 0.8 KJ/Kgk

    SV

    = ?

    S =Q

    mT

    SV Sl = 16.2 MJ

    0.00572 MJ KgKm273 10

    SV

    Sl= 5.72 KJ/KgK

    SV2 = 6.52 KJ/KgK

    51. For the truss shown in the fig. the forces F1and F2are 9 kN and 3 kN the force (in kN) in themember QS is

    2

    ST

    1.5 3

    3 3

    F1 F2

    R

    QP

    (a) 11.25 tension (b) 11.25 compression

    (c) 13.5 tension (d) 13.5 compression

    Sol. : (a)

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    1.5 m

    2 m

    3 m R

    9 kN

    3 mP

    Q

    3 kN

    S

    3 m 1.5 m

    9 kN

    FQS

    tan = 2 4

    1.5 3

    sin =4

    5

    cos =3

    5

    QSF sin = 9

    FQS

    = 5 459 KN4 4

    FQS

    = 11.25 KN (Tension)

    52. Consider a velocity field v k (y i x k) , whenn K is a const. The vorticity, Z. is

    (a) K (b) k

    (c) k/2 (d) K/2

    Sol. : (a)

    V = kyi kxk u ky, w kx, v 0

    Wz

    =v u

    x y

    k0 k

    53. A uniform slender rod (3 m length & 8 kg mass) is rotate in a vertical plan about a horizontal axis

    1 m from its ends as shown. the magnitude of the angular acceleration a (in rad/s2) of the rod at

    the position shown is

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    ER1 m 2 mSol. :

    Ic

    =2

    ML

    12

    I0 = Ic+ mx2

    1m

    1.5

    2m

    .5 m

    C0

    I0 =2

    2MLMx

    12

    =2

    28 38 0.5

    12

    = 8 Kg m2.

    T = I

    Torque T = mg x

    = 8 10 0.5

    = 40 Nm

    .5 m

    C

    mg

    =2

    2

    T 40Nm5 rad s= =

    I 8Kgm

    54. It is desired to avoid interference in a pair of spur gears having 20 pressure angle with increase in

    pinion to gear speed ratio, the min no. of teeth on the pinion.

    (a) Increase (b) decreases

    (c) first increase & then decrease (d) remain unchanged.

    Sol. : (a)

    Spur gear having 20 pressure angle

    Avoid Interference

    Minimum No. of teeth of Pinia = 229

    1 G sin 1G 2

    As G

    Denominator Decrease

    Minimum No. of teeth increases

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    55. Consider an ordinary differential eqn.dx

    dt= 4t + 4 if x = x

    0at t = 0, the increment in x calculated

    usign Runge-Kutta fourth order multi step method with a step size of t = 0.2 is

    (a) 0.12 (b) 0.44

    (c) 0.66 (d) 0.88

    Sol. : (d)

    d

    dt

    x= 4t + 4, x(0) = x

    0, t = h = 0.2

    f(t,x) = 4t + 4

    K1

    = hf(x

    0) = (0.2) (4) = 0.8

    K2

    = hf (0.1, x

    0+ 0.4) = (0.2) (0.4 + = 0.88

    K3

    = hf(0.2, x0+ 0.88) = (0.2) (0.8 + 4) = 0.96

    K = 1 2 3 41

    K 2K 2K K 6

    = 0.88

    1x = 0x + K = 0x + 0.88So increment inx= 0.88

    56. Which of the following option is closest in meaning. In a democracy, everybody has the freedom to

    disagreewith the goverment.

    (a) dissent (b) descent

    (c) decent (d) decadent

    Sol. : (a)

    57. In a sequence of 12 consecutive odd number the sum of the first 5 no. is 425. what is the sum of

    last 5 nos in the sequence.

    Sol. : 495

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    odd no.

    2

    4

    6

    8

    x

    x

    x

    x

    x

    10

    12

    x

    x

    14

    16

    18

    20

    22

    x

    x

    x

    x

    x

    5x + 2 + 4 + 8 + 6 = 425

    x =425 20 405

    815 5

    Sum of last 5 nos.

    5x + 14 + 16 + 18 + 20 + 22

    = 5 81 + 90

    = 405 + 90

    = 495

    58. While receiving the award the scientist said I feel vindicated, which of the following is closest in

    meaning to the word vindicated.

    (a) Panal (b) substantiated

    (c) Appreciated (d) Chatemal.

    Sol. : (b)

    59. Lt f(x,y) = xnym= P, if x is doubled and y is halved the new value of f is.

    (a) 2nmp (b) 2mnp

    (c) 2(nm) p (d) 2(mn) p

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    Sol. : (a)

    f(x, y) =xnym= p

    If xis doubled andyis halfed

    f(x, y) =

    mn n m n m n myx x y p(2 ) 2 2

    2

    60. After the discussion Tom said to my please revert ! He expects him to

    (a) retract (b) get back to him(c) more in reverse (d) retrect.

    Sol. : (b)

    61. A five digit no, is formed using the digit 1, 3, 5, 7, 9 without repeating any of them. What is the

    sum of all such possible five digit nos.?

    (a) 6666660 (b) 6666600

    (c) 666666 (d) 6666606

    Sol. : (b)

    62. If KCLFTSB, stands for best of luck and SHSWDG stands for good wishes. Which of the following

    indicates ace of the exam ?

    (a) MCHTX (b) MXHTC

    (c) XMHCT (d) XMKTC

    Sol. : (b)

    63. A f irm producing air purif ier sold 200 units in 2012. The following pie chart represents the share of

    raw materials, labour, energy, plant and machinery and transportation cost in the total manufacturing

    cost of the firm in 2012. The expenditure on labour in 2012 is Rs. 4,50,000. In 2013, the raw material

    expenses increase by 30% and all other expanses increases by 20%. What is the % increase in

    total cost of company in 2013.

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    Transportation

    Labour

    Material

    10%

    15%

    20%

    25%

    30%

    Energy

    Plant andmachinery

    Sol. : Let the total production cost bex in 2012.

    Hence515 4.5 10

    100

    x

    x =5

    54.5 10 100 30 1015

    Raw material cost in 2013 =5 201.3 30 10

    100

    = 7.8 105

    All other expanses in 2013 = 30 105 0.8 1.2

    = 28.8 105

    Total cost in 2013 = (28.8 + 7.8) 105

    = 36.6 105

    % increase in cost in 2013 =36.6 30

    10030

    =

    6.6

    0.3 = 22%

    64. Industrial consumption of power doubled from 2000-2001 to 2010-2011. Find the annual rate of

    increase in percent assuming it to be uniform over the years.

    (a) 5.6 (b) 7.2

    (c) 10.0 (d) 12.2

    Sol. : (b)

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    2a0

    =

    11 1

    0 1100

    ra

    r = 7.177%

    65. Find the next term in the sequence : 13 M, 17Q, 19S, ___

    (a) 21W (b) 21 V

    (c) 23W (d) 23 V

    Sol. : (c)

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