Mangalore Refinery and Petrochemicals Ltd(MRPL) Mechanical-Engineering Contributed by Srijin updated on Mar 2019

                                   MRPL Written Test Paper - Mechanical Engineering

1. Time dependent permanent deformation is called ________________.
(a) Plastic deformation 
(b) Elastic deformation
(c) Creep 
(d) Anelastic deformation

2. Figure-out the odd point in the following
(a) Proportinal limit 
(b) Elastic limit
(c) Yeild point 
(d) Fracture point

3. If a material is subjected to two incremental true strains namely ?1 and ?2, then the total true strain is
(a) ?1 * ?2 
(b) ?1 - ?2 
(c) ?1 + ?2
(d) ?1 / ?2

4. Engineering stress-strain curve and True stress-strain curve are equal up to
(a) Proportional limit 
(b) Elastic limit 
c) Yeild point 
(d) Tensile strength point

5. Value of Poisson’s ratio for ionic solids in the range of
(a) 0.1 
(b) 0.2 
(c) 0.3 
(d) 0.4

6. Hydrostatic stress results in the following
(a) Linear strain 
(b) Shear strain
(c) Both linear and shear strains 
(d) None

7. High elastic modulus in materials arises from
(a) High strength of bonds 
(b) Weak bonds
(c) combination of bonds 
(d) None

8. Change in elastic modulus for ordinary materials between 0K and melting point is
(a) 10-20% increase 
(b) 10-20% decrease
(c) 80-90% decrease 
(d) 80-90% increase

9. Bauschinger effect
(a) Hysteresis loss during loading and unloading
(b) Anelastic deformation
(c) Dependence of yield stress on path and direction
(d) None

10. Shape of true stress-strain curve for a material depends on
(a) Strain 
(b) Strain rate
(c) Temperature 
(d) All

11. Toughness of a material is equal to area under ____________ part of the stress-strain curve.
(a) Elastic 
(b) Plastic 
(c) Both 
(d) None

12. True stress-strain curve need to be corrected after
(a) Elastic limit 
(b) Yield limit
(c) Tensile strength 
(d) no need to correct

13. Following condition represents onset of necking
(a) ?u = n 
(b) ?u = 1-n 
(c) ?u = 1+n 
(d) ?u = ln (1+n)

14. As compared with conventional stress-strain curve, the true stress-strain curve is
(a) Above and right 
(b) Below and right
(c) Above and left 
(d) Below and left

15. According to distortion-energy criterion, yielding occurs when
(a) Distortion energy reaches a critical value
(b) Second invariant of the stress deviator exceeded some critical value
(c) Octahedral shear stress reaches a critical value
(d) All

16. von Mises and Tresca criteria give different yield stress for
(a) Uni-axial stress 
(b) Balanced bi-axial stress
(c) Pure shear stress 
(d) All

17. Plastic deformation results from the following
(a) Slip 
(b) Twinning 
(c) Both 
(d) None

18. Time dependent recoverable deformation under load is called ____________ deformation.
(a) Elastic
(b) Anelastic
(c) Elastic after-effect 
(d) Visco-elastic

19. For a Newtonian fluid:
(a) Shear stress is proportional to shear strain.
(b) Rate of Shear stress is proportional to shear strain.
(c)Shear stress is proportional to rate of shear strain.
(d) Rate of shear stress is proportional to rate of shear strain.

20. The number of inversions for a slider crank mechanism is
(a) 6
(b) 5
(c) 4
(d) 3

21. Dew point temperature is temperature at which condesation begins when the air is cooled at constant
(a) Volume
(b) Entropy
(c) pressure
(d) Enthalpy

22. In a pelton wheel, the bucket peripheral speed is 10m/s, the water jet velocity is 25m/s and volumetric flow rate of the jet is 0.1m3/s. If the jet deflection angle is 120 degrees and the flow is ideal, the power developed is
(a) 7.5 KW
(b)15.0 KW
(c)22.5 KW
(d) 37.5 KW

23. An expandable pattern is used in
(a) Slush Casting
(b) Squeeze casting
(c) Centrifugal Casting
(d) Investment Casting

24. The main purpose of spheroidising treatment is to improve
(a) hardenability of low carbon steels
(b) machinability of low carbon steels
(c) hardenability of high carbon steels
(d) machinability of high carbon steels

25. NC countering is an example of
(a) Continuous path positoning
(b) Point to point positioning
(c) Absolute positioning
(d) Incremental positioning

26. A ring gauge is used to measure
(a) outside roundness but not roundness
(b) roundness but not outside diameter
(c) both outside diameters and roundness
(d) only external threads

27. Match the items in columns I and II
Column I 
A. Addendum 
B.Instantaneous center of velocity 
C. Section Modulus 
D. Prime Circle 

Column II
1. Cam
2. Beam
3. Linkage
4. Gear

(a) A-4 B-2 C-3 D-1
(b) A-4 B-3 C-2 D-1
(a) A-3 B-2 C-1 D-4
(a) A-3 B-4 C-1 D-2

28. A disk clutch is required to transmit 5KW at 2000 rpm. The disk has a friction limit with coefficient of friction equal to 0.25 . bore radius of friction lining is equal to 25mm. Assume uniform contact pressure of 1MPa. The value of outside radius of the friction lining is:
(a) 39.4mm
(b) 49.5mm
(c) 97.9mm
(d) 142.9mm

29. Twenty degree full depth involute profiled 19-tooth pinion and 37 tooth gear are in mesh. If the module is 5mm, the center distance between gear pair will be
(a) 140 mm
(b) 150 mm
(c) 280 mm
(d) 300 mm

30. A large hydraulic turbine is to generate 300KW at 1000 rpm under a head of 40m. For initial testing, a 1:4 scale model of turbine operators under a head of 10m. The power generated by the model (in KW) will be
(a) 2.34
(b) 4.68
(c) 9.38
(d) 18.75

31. A steel bar of 40mm X 40mm square cross section is subjected to an axial compressive load of 200KN. IF the length of bar is 2m and E =200 GPa, the elongation of the bar will be
(a) 1.25mm
(b) 2.70mm
(c) 4.05mm
(d) 5.40mm

32. IF the Cf is the coefficient of speed fluctuation of flywheel then the ratio of w max/ w min will be
(a) (1-2Cf)/(1+2Cf)
(a) (2-cf)/(1+2Cf)
(a) (1+2Cf)/(1-2Cf)
(d) (2+Cf)(2-Cf)

33. If a system is in equilibrium and the position of system depends upon many independent variables, the principal of virtual work states that the partial derivatives of its total potential energy with repsect to each of the independent variable must be
(a) -1.0
(b) 0
(c) 1.0

34. Match the items in Column I and Column II
Column I 
P.Higher kinematic pair 
Q. Lower Kinematic pair 
R. Quick Return Mechanism 
S. Mobility of a linkage 

Column II
1. Grubler’s Equation
2. Line Contact
3. Euler’s equation
4. Planer
5. Shaper
6. Surface contact

(a) P-2,Q-6,R-4,S-3
(b) P-6,Q-2,R-4,S-1
(c) P-6,Q-2,R-5,S-3
(d) P-2,Q-6,R-5,S-1

35. A machine of 250kg mass is supported on springs of total stifness 100 KN/m. Machine has an unbalanced rotating force of 350 N at speed of 3600 rpm. Assume a damping factor of 0.15, the value of transmissibility ratio is
(a) 0.0531
(b) 0.9922
(c) 0.0162
(d) 0.0028

36. A 60mm long and 6mm thick fillet weld carries a steady load of 15KN along the weld. The shear strength of weld material is equal to 200MPa. The factor of safety is
(a) 2.4
(b) 3.4
(c) 4.8
(d) 6.8

37. A two dimensional flow field has velocities along the x and y directions given by u= x2t and v= -2xyt respectively where t is time. The equation of streamlines is
(a) x2y= Constant
(b) xy2= Constant
(c) xy = Constant
(d) not possible to determine

38. The velocity profile in fully developed laminar flow in a pipe of diameter D is given by u=u0(1-4r2/D2), where r is radial distance from the center. If the viscosity of the fluid is µ, The pressure drop across a length L of the pipe is
(a) (µu0L)/D2
(b) 4(µu0L)/D2
(c) 8(µu0L)/D2
(d) 16(µu0L)/D2