Provided by www.YuvaJobs.com - Technical - Other Hyderabad - 30 June 2005 ISRO SAMPLE PAPER ON 30th JUNE 2005 AT HYDERABAD    Hi friends,                   Written Test for Scientist / Engineer_SC :  [ Mechanical Engineering ] Date: 30-06-2005 Place: St. Anne¡¯s School, Hyderabad.                                         Question Pattern for Written Examination ¨ª      80 Questions ¨ª      2.00 hrs Duration ¨ª      ¨ù Negative Marks ¨ª      All are Objective & Multiple choice Questions.    1  The concept  of  ---------------------------------- derived from the ¡°ZEROTH LAW OF THERMODYNAMICS¡±.                                                                               TEMPERATURE  2  The concept of  ------------------------------------- derived from the ¡°SECOND LAW OF THERMODYNAMICS¡±.                                                                               ENTROPY  3  The expression for  isentropic index [¥ã] in terms of number of degrees of freedom ( n ) ------------------------                                                                         1+ [ 2 / n]  4  The critical  Reynolds no upto which the viscous flow exists in pipe  -------------------                                                                                                                                          2000  5   Two forces  of equal magnitude P acts at right angles to each other and having  same directions. Find out the expression for their resultant [R ]--------------------                                                                          [2]¨ö P  6  The angular frequency of handclock------------------                                                                                 ¥Ð/30 rad/s 7   The equation for free torsional vibration----------------------------                                                                                 [1/2¥Ð] [q/I]¨ö                                                                            8    A thin cylinder is subjected to longitudinal stress ¥ò0 and internal pressure P , findout the maximum shearstress developed in it [ q max]  ------------------------                                                                                                          0.5 ¥ò0 9  Rate of moment of momentum is equal to the -------------------------                                                                               Torque applied by the body  10  The expression for loss of energy [he ] due to sudden enlargement of the pipe--------                                                                                   he =[v1-v2]©÷/2g                                                                                 11  A spring of stiffness K is divided into ¡°n¡± number of springs. Each spring having stiffness ---------------------------                                                                   nK  12 The non-dimensional number corresponds to                                     [inertia force\compressibility force]¨ö------------------------------                                                           Euler number  13 Equation for forced vortex flow-----------------------------                                                                            v/r = constant  14 The causes of cavitation Metallic surfaces are damaged Noise & vibrations  15  How to increase the thermal efficiency in Carnot cycle by-------------------------------                                                                    Decreasing low temperature  16  The slenderness ratio in columns can be obtained from the ---------------                                                          Least radius of gyration   17   50:1 gear reduction ratio possible in-----------------                                                               worm gear 18  Wire drawing property named as -------------------------                                                  ductility  19  One man is standing in the elevator and the elevator is moving in the upward direction. What type of reading regarding the weight of man will we get from gauge---------------                                                           The weight of man shown by the gauge will more the actual weight of the man.  20   LMTD for counterflow heat exchanger is compared to parallel to heat exchanger-----                                                                                    More 21   The free damping equation  2y¨¬¨¬ +  3y¨¬ +8y =0. Calculate  damping factor (D.F )--------                                                                                                 3/8   22  The discharges for  the two parallel pipes of same lengths are  Q1 & Q2 respectively and their diameters are 200 mm & 800 mm respectively. Calculate the  ratio of discharge of smaller pipe to larger pipe.                                                                 1/32  23  A compressor is used to compress the air from 5 bar to 10 bar .Calculate its critical pressure [ P٭]----------------------                                                                  2.64 bar  24   Equivalent twisting moment------------------------------                                                                            Te = [T©÷ + M©÷]¨ö  25  The shear stress distribution in pipe flow -----------------------------                                                                             Centre is zero and linearly varying from the center to the wall  26   The irrational component in x-y is--------------                                                           ¥äv/¥äx = ¥äu/¥äy  27 The ratio kinetic viscosity/thermal diffusivity is -------------                                                                              Nusselt Number   28   The cylinder is subjected to insulations K & 2K  at the outside surface to avoid heat transfer. In order to arrest heat transfer effectively , which insulation should be provided first at the outer surface?                                                              2K & K respectively   29  The wall having conductivities K1      K2  Findout the equivalent conductivity of the material--------------------?   29   The maximum amplitude in this vibration equation y = 6 sin¥øt    --------                                                 6  30   The thermal boundary layer in an ideal fluid flow is --------------                                                                    0  31  What does tend to stagnation point -----------------------                                                          The velocity is 0 at the stagnation point due to the increase in pressure energy from the conversion of K.E into P.E.  32    Match the following:            i.            subsonic nozzle                           :  figure          ii.            Supersonic nozzle                        :  figure         iii.            Subsonic diffuser                          : figure        iv. Centrifugal compressor                 :  figure   33   The factor of safety subjected to number of cycles related to                                                                  Endurance limit  34   In composite beam , width is directly proportional to ----------------------------------- if the depth of the beam is kept constant.                                                                             ¥á M  35   The heat transfer rate of hollow cylinder is inversly proportional to the following ---------------------------------                     r2/r1                                                                                     36  A material  at 300¨¬C is immersed in  water at 30¨¬C such that it will take  170 seconds to become 150¨¬C . A same material at 300¨¬C is put in air at 30¨¬C but  it will take 200 seconds to become 150¨¬C. What is the reason behind it ?                                                                K of water is more compared to air  37  Radiation is ------------------------------------------ wave phenomenon                                                                Electromagnetic without medium   38  The compression ratio[r] of petrol engine ranges from -------------------                                                                  6 to 10   39  ¡ò¥äQ/T =0 and ¥Äs=0 corresponds to ----     irreversible & adiabatic 40      Cold working of metal increases ----------------------                                             Tensile strength   41   The power absorbed in belt drive depends on-----------------------                                                         Tension in tight side, Tension in slack side, coefficient of friction & Radius of pulley.   42   The temperature loss related -------------- hysteresis loss   43    The convergent pipe having entry and exit diameters are 100 and 50 mm respectively, find out their velocity ratio from entry to exit¡¦¡¦¡¦¡¦..                                                           1/4  44   They had given one composite circular pipe having 4 varying cross sections . They are 2D, 1.5D, 4D & D respectively. The water is entering at velocity V at section 1 and leaving at section 4. Find out the pressure decreasing order¡¦¡¦¡¦¡¦¡¦                                                            P4>P2>P1>P3   45  The bulb having weight 150N supported by two ropes and attached to the walls having angles 45¨¬ & 60¨¬. Findout the reaction forces in the ropes ?                          This is related to Lamis theorem   46  A hollow sphere of radius r . A particle is moving with coefficient of friction 1/[3]¨ö inside the sphere from wall . which height will it become rest?                                                      47   The disc is resting on the rough wall by a rope tied at the center . The rope makes angle with the wall around 30¨¬. The tension in the string is ----------than the weight of the disc.                                          more   48  A railway wagon containing partially full of water. Which angle----------------                                                       49   Findout the graph between discharge [Q] in the x-axis and head [H] in the y-axis----------                                                50  In welding pitch dimension is limited to----------------------   51  The composition of inconel alloy-------------------  52  There is a heat transfer between two walls having thickness  and  conductivities k1 & K2 respectively. The linear temperature  profile of first wall is more steeper than the second wall . Findout the ratio K1/K2  --------------------- a) >0         b) <0       c)=0  d) the given data is insufficient   53  The max shear stress developed in solid circular shaet is 100 MPa . Calculate the max normal stress developed in it?            ??????   54  This question related to welding -------------   55  Bearing liner-------------------------  a) Babbit metal b) Gun metal   56   Electrical resistance material --------------Nichrome   57  This question related to radiation   58  A sun emits 1150K at 0.5¥ì. A furnace emits 300k from small door --------------    59    In the simple pendulum , the maximum amplitude depends on -------------------         increase in length   60   The fuel flow increases if-------------------------                         a) exhaust valve burnt b) filter choke c) silencer choke 61    The jet propulsion depends on------------- a)      jet velocity b) weight ratio   62     What is the condition for perfect frame-------------------------------------   63     Depth of cut can be increased by-----------------------   64     The workpiece can be held in-----------------   65    This is related toNucleate boiling   66    What is the expression for Reynolds number in terms of diameter of the pipe¡¦¡¦¡¦¡¦..Re =¥ñVD/¥ì   67    Air conditioning means--------------- a)      cooling & heating b)dehumidifying c) removing impurities from air d)all  68  Fibrous fracture occurs in ------------------------ a)brittle fracture b) ductile fracture c)shear fracture d)none   69   In laser beam machining , the workpiece should be-------------- a)absorbed by all the rays b) reflected by all the rays   70   Foam and coke are good insulators. Why?----------------------- a)less density b)   71   Gold property------------------ a)good conductor b)good insulator   72   In lathe , the workpiece can be held in -------------------------------------- a) live center  b)steady rest  c)3-way chuck  d)4-way chuck                                        INTERVIEW PATTERN                 I.      Project Explanation              II.      Fluid Mechanics:                                  i.            Define laminar flow & Turbulent flow                                ii.            What is the value of Reynolds no in pipe flow                               iii.            What is the significance of Reynolds no                              iv.            Head losses in pipe                                v.            Define boundary layer in pipe flow & thickness of boundary layer                              vi.            What is the variation of ¥ä in laminar & turbulent flow            III.      Strength of materials                            i.            Draw the figure for spring damper system                          ii.            Differential equation for spring damper system                         iii.            Find out the deflection of spring damper system                        iv.            Define stiffness and unit of stiffness           IV.      Material Science                              i.            Ferrous materials                            ii.            Non-ferrous materials                           iii.            Define fatigue                          iv.            Define fatigue resistance?                            v.            Curve for fatigue                          vi.            Fatigue limit   Provided by www.YuvaJobs.com - Technical - Other Hyderabad - 30 June 2005