MECHANICAL ENGINEERING- PAGE 15
Mechanical Engineering MCQs- Page 15
1. Alcohols are unsuitable as diesel engine fuels because
(A) The cetane number of alcohol fuels is very low which prevents their ignition by compression
(B) The cetane number of alcohol fuels is very high which prevents their ignition by compression
(C) The octane number of alcohol fuels is very low which prevents their ignition by compression
(D) None of the above
Ans: A
2. What is the flash point of a liquid fuel?
(A) The temperature at which the fuel ignites spontaneously with a bang
(B) The temperature at which the fuel emits vapours at a rate which produces an inflammable mixture with air
(C) The temperature at which the fuel ignites with a clear flame
(D) The temperature at which the fuel ignites without a spark
Ans: B
3. A 40 kW engine has a mechanical efficiency of 80%. If the frictional power is assumed to be constant with load, what is the approximate value of the mechanical efficiency at 50% of the rated load?
(A) 45% (B) 55% (C) 65% (D) 75%
Ans: C
4. Which one of the following set of materials is most commonly used in catalytic converters for CI engines?
(A) Platinum, palladium and rhodium (B) Palladium, rhodium and ruthenium
(C) Rhodium, ruthenium and platinum (D) Ruthenium, platinum and palladium
Ans: A
5. The three way catalytic converter cannot control which one of the following?
(A) HC emission (B) CO emission (C) NOx emission (D) PM emission
Ans: D
6. The Vahan and Sarathi are conceptualized to capture the functionality as mandated by which Act :
(A) Central Motor Vehicle Act, 1988 (B) Central Motor Vehicle Act, 1999
(C) Central Motor Vehicle Act, 1989 (D) None of the above
Ans: A
7. Which rule has been amended to standardise the form and the manner in which registration numbers are displayed in the country:
(A) Central Motor Vehicle rule, 1988 (B) Central Motor Vehicle rule, 1999
(C) Central Motor Vehicle rule, 1989 (D) None of the above
Ans: C
8. Which Logic circuit would you use for addressing memory?
(A) Full adder (B) Multiplexer (C) Decoder (D) Direct memory access circuit
Ans: C
9. A Flip-Flop circuit can be used for
(A) Counting (B) Scaling (C) Rectification (D) Demodulation
Ans: A
10. Library function pow() belongs to which header file?
(A) mathio.h (B) math.h (C) square.h (D) stdio.h
Ans: B
11. The communication between central system and the outside environment is done by:
(A) Control system (B) Logic system (C) Memory system (D) I/O subsystem
Ans: D
12. In a SI Engine, which one of the following is the correct order of the fuels with increasing detonation tendency?
(A) Paraffins, Olefins, Naphthenes, Aromatics (B) Aromatics, Naphthenes, Paraffins, Olefins
(C) Naphthenes, Olefins, Aromatics, Paraffins (D) Aromatics, Naphthenes, Olefins, Paraffins
Ans: D
13. In a variable speed S.I. engine, the maximum torque occurs at the maximum
(A) Speed (B) brake power (C) Indicated power (D) volumetric efficiency
Ans: C
14. In a Morse test for a 2-cylinder, 2-stroke, spark ignition engine, the brake power was 9 kW whereas the brake powers of individual cylinders with spark cut off were 4.25 kW and 3.75 kW respectively. The mechanical efficiency of the engine is
(A) 90% (B) 80% (C) 45.5% (D) 52.5%
Ans: A
15. Degree of reaction is defined as the ratio of
(A) Enthalpy drop in moving blades to enthalpy drop in fixed blades
(B) Enthalpy drop in fixed blades to total enthalpy drop in moving and fixed blades
(C) Enthalpy drop in fixed blades to enthalpy drop in moving blades
(D) Enthalpy drop in moving blades to total enthalpy drop in fixed and moving blades
Ans: D
16. Which one of the following cycles has the highest thermal efficiency for given maximum and minimum cycle temperatures?
(A) Brayton cycle (B) Otto cycle (C) Diesel cycle (D) Stirling cycle
Ans: D
17. With respect to computer applications CISC stands for
(A) Compound Instruction Set Computers (B) Common Instruction Set Computers
(C) Complex Instruction Set Computers (D) Complex Instruction Set Compilers
Ans: C
18. The mechanism used in a shaping machine is
(A) a closed 4-bar chain having 4 revolute pairs
(B) a closed 6-bar chain having 6 revolute pairs
(C) a closed 4-bar chain having 2 revolute and 2 sliding pairs
(D) an inversion of the single slider-crank chain
Ans: D
19. The lengths of the links of a 4-bar linkage with revolute pairs only are p, q, r and s units. Given that p < q < r < s. Which of these links should be the fixed one, for obtaining a ‘double crank’ mechanism?
(A) link of length p (B) link of length q (C) link of length r (D) link of length s
Ans: A
20. In a spring-mass system, the mass is 0.1 kg and the stiffness of the spring is 1 kN/m. By introducing a damper, the frequency of oscillation is found to be 90% of the original value. What is the damping coeffcient of the damper?
(A) 1.2 Ns/m (B) 3.4 Ns/m (C) 8.7 Ns/m (D) 12.0 Ns/m
Ans: C
21. The speed of an engine varies from 210 rad/s to 190 rad/s. During a cycle, the change in kinetic energy is found to be 400 Nm. The inertia of the flywheel in kg·m2 is
(A) 0.10 (B) 0.20 (C) 0.30 (D) 0.40
Ans: A
22. Global warming is caused by
(A) Ozone (B) Carbon dioxide (C) Nitrogen (D) Carbon monoxide
Ans: B
23. Anti-friction bearings are
(A) sleeve bearings (B) gas lubricated bearings
(C) ball and roller bearings (D) journal bearings
Ans: C
24. A concentrated load of P acts on a simply supported beam of span L at a distance L/3 from the left support. The bending moment at the point of application of the load is given by
(A) PL/3 (B) 2PL/3 (C) PL/9 (D) 2PL/9
Ans: D
25. A simply supported laterally loaded beam was found to deflect more than a specified value. Which of the following measures will reduce the deflection?
(A) Increase the area moment of inertia (B) Increase the span of the beam
(C) Select a different material having lesser modulus of elasticity (D) Magnitude of the load to be increased
Ans: A
26. In terms of Poisson’s ratio (ν), the ratio of Young’s modulus (E) to Shear modulus (G) of elastic materials is
(A) 2(1+ν) (B) 2(1−ν) (C) (1+ν)/2 (D) (1−ν)/2
Ans: A
27. If the principal stresses in a plane stress problem are σ1 = 100 MPa, σ2 = 40 MPa, the magnitude of the maximum shear stress (in MPa) will be
(A) 60 (B) 50 (C) 30 (D) 20
Ans: C
28. For a long slender column of uniform cross-section, the ratio of critical buckling load for the case with both ends clamped to the case with both ends hinged is
(A) 1 (B) 2 (C) 4 (D) 8
Ans: C
29. A long thin-walled cylindrical shell, closed at both ends, is subjected to an internal pressure. The ratio of the hoop stress (circumferential stress) to longitudinal stress developed in the shell is
(A) 0.5 (B) 1.0 (C) 2.0 (D) 4.0
Ans: C
30. A thin cylinder of inner radius 500 mm and thickness 10 mm is subjected to an internal pressure of 5 MPa. The average circumferential (hoop) stress in MPa is
(A) 100 (B) 250 (C) 500 (D) 1000
Ans: B
31. A planar closed kinematic chain is formed with rigid links PQ= 2.0 m, QR= 3.0 m, RS= 2.5 m and SP= 2.7 m with all revolute joints. The link to be fixed to obtain a double rocker (rocker–rocker) mechanism is
(A) PQ (B) QR (C) RS (D) SP
Ans: C
32. The element with the lowest density and smallest atomic weight is which one of the following?
(A) aluminum (B) argon (C) helium (D) hydrogen
Ans: D
33. Which one of the following materials is closest to diamond in hardness?
(A) aluminum oxide (B) carbon dioxide (C) cubic boron nitride (D) silicon dioxide
Ans: C
34. Anisotropic means which one of the following:
(A) composite materials with composition consisting of more than two materials
(B) properties are the same in every direction
(C) properties vary depending on the direction in which they are measured
(D) strength and other properties as a function of curing temperature.
Ans: C
35. In white cast irons, carbon present as
(A) Graphite flakes (B) Graphite nodules (C) Cementite (D) Carbon does not exist
Ans: C
36. Increased cooling rate in the heat treatment of mild steel results into
(A) Coarse pearlite (B) Fine pearlite (C) Heat treatment does not affect the pearlite morphology (D) Mixture of fine and coarse pearlite
Ans: B
37. During heat treatment of steel, the hardness of various structures in increasing order is
(A) martensite, fine pearlite, coarse pearlite, spheroidite (B) fine pearlite, coarse pearlite, spheroidite, martensite
(C) martensite, coarse pearlite, fine pearlite, spheroidite (D) spheroidite, coarse pearlite, fine pearlite, martensite
Ans: D
38. Tool geometry of a single point cutting tool is specified by the following elements:
1. Back rake angle (αb)
2. Side rake angle (αs)
3. End cutting edge angle (φ)
4. Side cutting edge angle (ψ)
5. Side relief angle (cs)
6. End relief angle (cb)
7. Nose radius (r)
The correct sequence of these tool elements used for correctly specifying tool geometry is
(A) 1, 2, 3, 6, 5, 4, 7 (B) 1, 2, 6, 5, 3, 4, 7
(C) 1, 2, 5, 6, 3, 4, 7 (D) 1, 2, 6, 3, 5, 4, 7
Ans: B
39. The predominant phase in the iron-carbon alloy system for a composition with 99% Fe at room temperature is which of the following? (A) austenite (B) cementite (C) delta (D) ferrite
Ans: D
40. Plain carbon steels are designated in the AISI code system by which of the following?
(A) 01XX (B) 10XX (C) 11XX (D) 12XX
Ans: B
41. Which of the following is not a common alloying ingredient in steel?
(A) carbon (B) chromium (C) nickel (D) molybdenum
Ans: A
42. Which of the following has the lowest melting point?
(A) aluminum (B) lead (C) magnesium (D) tin
Ans: D
43. The number of inversions for a slider crank mechanism is
(A) 6 (B) 5 (C) 4 (D) 3
Ans: C
44. A planar mechanism has 8 links and 10 rotary joints. The number of degrees of freedom of the mechanism using Gruebler’s criterion, is (A) 0 (B) 1 (C) 2 (D) 3
Ans: B
45. There are two points P and Q on a planar rigid body. The relative velocity between the two points
(A) should always be along PQ
(B) can be oriented along any direction
(C) should always be perpendicular to PQ
(D) should be along QP when the body undergoes pure translation
Ans: C
46. Which of the following statements is incorrect?
(A) Grashof’s rule states that for a planar crank rocker four-bar mechanism, the sum of the shortest and longest link lengths cannot be less than the sum of the remaining two link lengths.
(B) Inversions of a mechanism are created by fixing different links one at a time.
(C) Geneva mechanism is an intermittent motion device
(D) Gruebler’s criterion assumes mobility of a planar mechanism to be one.
Ans: A
47. The air standard efficiency of Diesel cycle will be less than that of Otto cycle in the case of
(A) Same compression ratio and same heat input (B) Same maximum pressure and same heat input
(C) Same maximum pressure and same heat output (D) Same maximum pressure and same maximum temperature
Ans: A
48. Assertion (A): In SI engines, as the engine speed increases, spark is required to be advanced.
Reason (R): As the engine speed increases, flame velocity increases.
(A) Both A and R are individually true and R is the correct explanation of A
(B) Both A and R are individually true but R is not the correct explanation of A
(C) A is true but R is false
(D) A is false but R is true
Ans: C
49. At the time of starting, idling and low speed operation, the carburettor supplies a mixture which can be termed as
(A) Lean (B) slightly leaner than stoichiometric (C) stoichiometric (D) rich
Ans: D
50. Assertion (A): The carburettor in a petrol engine is categorized as a closed loop control system.
Reason (R): There is no method by which the air-fuel ratio is measured in the carburettor.
(A) Both A and R are individually true and R is the correct explanation of A
(B) Both A and R are individually true but R is not the correct explanation of A
(C) A is true but R is false (D) A is false but R is true
Ans: C
(A) The cetane number of alcohol fuels is very low which prevents their ignition by compression
(B) The cetane number of alcohol fuels is very high which prevents their ignition by compression
(C) The octane number of alcohol fuels is very low which prevents their ignition by compression
(D) None of the above
Ans: A
2. What is the flash point of a liquid fuel?
(A) The temperature at which the fuel ignites spontaneously with a bang
(B) The temperature at which the fuel emits vapours at a rate which produces an inflammable mixture with air
(C) The temperature at which the fuel ignites with a clear flame
(D) The temperature at which the fuel ignites without a spark
Ans: B
3. A 40 kW engine has a mechanical efficiency of 80%. If the frictional power is assumed to be constant with load, what is the approximate value of the mechanical efficiency at 50% of the rated load?
(A) 45% (B) 55% (C) 65% (D) 75%
Ans: C
4. Which one of the following set of materials is most commonly used in catalytic converters for CI engines?
(A) Platinum, palladium and rhodium (B) Palladium, rhodium and ruthenium
(C) Rhodium, ruthenium and platinum (D) Ruthenium, platinum and palladium
Ans: A
5. The three way catalytic converter cannot control which one of the following?
(A) HC emission (B) CO emission (C) NOx emission (D) PM emission
Ans: D
6. The Vahan and Sarathi are conceptualized to capture the functionality as mandated by which Act :
(A) Central Motor Vehicle Act, 1988 (B) Central Motor Vehicle Act, 1999
(C) Central Motor Vehicle Act, 1989 (D) None of the above
Ans: A
7. Which rule has been amended to standardise the form and the manner in which registration numbers are displayed in the country:
(A) Central Motor Vehicle rule, 1988 (B) Central Motor Vehicle rule, 1999
(C) Central Motor Vehicle rule, 1989 (D) None of the above
Ans: C
8. Which Logic circuit would you use for addressing memory?
(A) Full adder (B) Multiplexer (C) Decoder (D) Direct memory access circuit
Ans: C
9. A Flip-Flop circuit can be used for
(A) Counting (B) Scaling (C) Rectification (D) Demodulation
Ans: A
10. Library function pow() belongs to which header file?
(A) mathio.h (B) math.h (C) square.h (D) stdio.h
Ans: B
11. The communication between central system and the outside environment is done by:
(A) Control system (B) Logic system (C) Memory system (D) I/O subsystem
Ans: D
12. In a SI Engine, which one of the following is the correct order of the fuels with increasing detonation tendency?
(A) Paraffins, Olefins, Naphthenes, Aromatics (B) Aromatics, Naphthenes, Paraffins, Olefins
(C) Naphthenes, Olefins, Aromatics, Paraffins (D) Aromatics, Naphthenes, Olefins, Paraffins
Ans: D
13. In a variable speed S.I. engine, the maximum torque occurs at the maximum
(A) Speed (B) brake power (C) Indicated power (D) volumetric efficiency
Ans: C
14. In a Morse test for a 2-cylinder, 2-stroke, spark ignition engine, the brake power was 9 kW whereas the brake powers of individual cylinders with spark cut off were 4.25 kW and 3.75 kW respectively. The mechanical efficiency of the engine is
(A) 90% (B) 80% (C) 45.5% (D) 52.5%
Ans: A
15. Degree of reaction is defined as the ratio of
(A) Enthalpy drop in moving blades to enthalpy drop in fixed blades
(B) Enthalpy drop in fixed blades to total enthalpy drop in moving and fixed blades
(C) Enthalpy drop in fixed blades to enthalpy drop in moving blades
(D) Enthalpy drop in moving blades to total enthalpy drop in fixed and moving blades
Ans: D
16. Which one of the following cycles has the highest thermal efficiency for given maximum and minimum cycle temperatures?
(A) Brayton cycle (B) Otto cycle (C) Diesel cycle (D) Stirling cycle
Ans: D
17. With respect to computer applications CISC stands for
(A) Compound Instruction Set Computers (B) Common Instruction Set Computers
(C) Complex Instruction Set Computers (D) Complex Instruction Set Compilers
Ans: C
18. The mechanism used in a shaping machine is
(A) a closed 4-bar chain having 4 revolute pairs
(B) a closed 6-bar chain having 6 revolute pairs
(C) a closed 4-bar chain having 2 revolute and 2 sliding pairs
(D) an inversion of the single slider-crank chain
Ans: D
19. The lengths of the links of a 4-bar linkage with revolute pairs only are p, q, r and s units. Given that p < q < r < s. Which of these links should be the fixed one, for obtaining a ‘double crank’ mechanism?
(A) link of length p (B) link of length q (C) link of length r (D) link of length s
Ans: A
20. In a spring-mass system, the mass is 0.1 kg and the stiffness of the spring is 1 kN/m. By introducing a damper, the frequency of oscillation is found to be 90% of the original value. What is the damping coeffcient of the damper?
(A) 1.2 Ns/m (B) 3.4 Ns/m (C) 8.7 Ns/m (D) 12.0 Ns/m
Ans: C
21. The speed of an engine varies from 210 rad/s to 190 rad/s. During a cycle, the change in kinetic energy is found to be 400 Nm. The inertia of the flywheel in kg·m2 is
(A) 0.10 (B) 0.20 (C) 0.30 (D) 0.40
Ans: A
22. Global warming is caused by
(A) Ozone (B) Carbon dioxide (C) Nitrogen (D) Carbon monoxide
Ans: B
23. Anti-friction bearings are
(A) sleeve bearings (B) gas lubricated bearings
(C) ball and roller bearings (D) journal bearings
Ans: C
24. A concentrated load of P acts on a simply supported beam of span L at a distance L/3 from the left support. The bending moment at the point of application of the load is given by
(A) PL/3 (B) 2PL/3 (C) PL/9 (D) 2PL/9
Ans: D
25. A simply supported laterally loaded beam was found to deflect more than a specified value. Which of the following measures will reduce the deflection?
(A) Increase the area moment of inertia (B) Increase the span of the beam
(C) Select a different material having lesser modulus of elasticity (D) Magnitude of the load to be increased
Ans: A
26. In terms of Poisson’s ratio (ν), the ratio of Young’s modulus (E) to Shear modulus (G) of elastic materials is
(A) 2(1+ν) (B) 2(1−ν) (C) (1+ν)/2 (D) (1−ν)/2
Ans: A
27. If the principal stresses in a plane stress problem are σ1 = 100 MPa, σ2 = 40 MPa, the magnitude of the maximum shear stress (in MPa) will be
(A) 60 (B) 50 (C) 30 (D) 20
Ans: C
28. For a long slender column of uniform cross-section, the ratio of critical buckling load for the case with both ends clamped to the case with both ends hinged is
(A) 1 (B) 2 (C) 4 (D) 8
Ans: C
29. A long thin-walled cylindrical shell, closed at both ends, is subjected to an internal pressure. The ratio of the hoop stress (circumferential stress) to longitudinal stress developed in the shell is
(A) 0.5 (B) 1.0 (C) 2.0 (D) 4.0
Ans: C
30. A thin cylinder of inner radius 500 mm and thickness 10 mm is subjected to an internal pressure of 5 MPa. The average circumferential (hoop) stress in MPa is
(A) 100 (B) 250 (C) 500 (D) 1000
Ans: B
31. A planar closed kinematic chain is formed with rigid links PQ= 2.0 m, QR= 3.0 m, RS= 2.5 m and SP= 2.7 m with all revolute joints. The link to be fixed to obtain a double rocker (rocker–rocker) mechanism is
(A) PQ (B) QR (C) RS (D) SP
Ans: C
32. The element with the lowest density and smallest atomic weight is which one of the following?
(A) aluminum (B) argon (C) helium (D) hydrogen
Ans: D
33. Which one of the following materials is closest to diamond in hardness?
(A) aluminum oxide (B) carbon dioxide (C) cubic boron nitride (D) silicon dioxide
Ans: C
34. Anisotropic means which one of the following:
(A) composite materials with composition consisting of more than two materials
(B) properties are the same in every direction
(C) properties vary depending on the direction in which they are measured
(D) strength and other properties as a function of curing temperature.
Ans: C
35. In white cast irons, carbon present as
(A) Graphite flakes (B) Graphite nodules (C) Cementite (D) Carbon does not exist
Ans: C
36. Increased cooling rate in the heat treatment of mild steel results into
(A) Coarse pearlite (B) Fine pearlite (C) Heat treatment does not affect the pearlite morphology (D) Mixture of fine and coarse pearlite
Ans: B
37. During heat treatment of steel, the hardness of various structures in increasing order is
(A) martensite, fine pearlite, coarse pearlite, spheroidite (B) fine pearlite, coarse pearlite, spheroidite, martensite
(C) martensite, coarse pearlite, fine pearlite, spheroidite (D) spheroidite, coarse pearlite, fine pearlite, martensite
Ans: D
38. Tool geometry of a single point cutting tool is specified by the following elements:
1. Back rake angle (αb)
2. Side rake angle (αs)
3. End cutting edge angle (φ)
4. Side cutting edge angle (ψ)
5. Side relief angle (cs)
6. End relief angle (cb)
7. Nose radius (r)
The correct sequence of these tool elements used for correctly specifying tool geometry is
(A) 1, 2, 3, 6, 5, 4, 7 (B) 1, 2, 6, 5, 3, 4, 7
(C) 1, 2, 5, 6, 3, 4, 7 (D) 1, 2, 6, 3, 5, 4, 7
Ans: B
39. The predominant phase in the iron-carbon alloy system for a composition with 99% Fe at room temperature is which of the following? (A) austenite (B) cementite (C) delta (D) ferrite
Ans: D
40. Plain carbon steels are designated in the AISI code system by which of the following?
(A) 01XX (B) 10XX (C) 11XX (D) 12XX
Ans: B
41. Which of the following is not a common alloying ingredient in steel?
(A) carbon (B) chromium (C) nickel (D) molybdenum
Ans: A
42. Which of the following has the lowest melting point?
(A) aluminum (B) lead (C) magnesium (D) tin
Ans: D
43. The number of inversions for a slider crank mechanism is
(A) 6 (B) 5 (C) 4 (D) 3
Ans: C
44. A planar mechanism has 8 links and 10 rotary joints. The number of degrees of freedom of the mechanism using Gruebler’s criterion, is (A) 0 (B) 1 (C) 2 (D) 3
Ans: B
45. There are two points P and Q on a planar rigid body. The relative velocity between the two points
(A) should always be along PQ
(B) can be oriented along any direction
(C) should always be perpendicular to PQ
(D) should be along QP when the body undergoes pure translation
Ans: C
46. Which of the following statements is incorrect?
(A) Grashof’s rule states that for a planar crank rocker four-bar mechanism, the sum of the shortest and longest link lengths cannot be less than the sum of the remaining two link lengths.
(B) Inversions of a mechanism are created by fixing different links one at a time.
(C) Geneva mechanism is an intermittent motion device
(D) Gruebler’s criterion assumes mobility of a planar mechanism to be one.
Ans: A
47. The air standard efficiency of Diesel cycle will be less than that of Otto cycle in the case of
(A) Same compression ratio and same heat input (B) Same maximum pressure and same heat input
(C) Same maximum pressure and same heat output (D) Same maximum pressure and same maximum temperature
Ans: A
48. Assertion (A): In SI engines, as the engine speed increases, spark is required to be advanced.
Reason (R): As the engine speed increases, flame velocity increases.
(A) Both A and R are individually true and R is the correct explanation of A
(B) Both A and R are individually true but R is not the correct explanation of A
(C) A is true but R is false
(D) A is false but R is true
Ans: C
49. At the time of starting, idling and low speed operation, the carburettor supplies a mixture which can be termed as
(A) Lean (B) slightly leaner than stoichiometric (C) stoichiometric (D) rich
Ans: D
50. Assertion (A): The carburettor in a petrol engine is categorized as a closed loop control system.
Reason (R): There is no method by which the air-fuel ratio is measured in the carburettor.
(A) Both A and R are individually true and R is the correct explanation of A
(B) Both A and R are individually true but R is not the correct explanation of A
(C) A is true but R is false (D) A is false but R is true
Ans: C
51. Which among the NC operations given below are continuous path operations?
Arc welding (AW)
Milling (M)
Drilling (D)
Punching of sheet metal (P)
Laser cutting of sheet metal (LC)
Spot welding (SW)
(A) AW, LC and M
(B) AW, D, LC and M
(C) D, LC, P and SW
(D) D, LC and SW
Ans: A
52. A shell of 100 mm diameter and 100 mm height with the corner radius of 0.4 mm is to be produced by cup drawing. The required blank diameter is
(A) 118 mm (B) 161 mm (C) 224 mm (D) 312 mm
Ans: C
53. In cold working,
(A) strength, hardness and ductility increase (B) strength and hardness increase, but ductility decreases
(C) strength, hardness and ductility decrease (D) strength and hardness decrease, but ductility increases
Ans: B
54. The word kanban is most closely associated with which one of the following?
(A) capacity planning (B) economic order quantity (C) just-in-time production (D) master production schedule
Ans: C
55. When the elements of net evaluation row of simplex table are equal, the situation is known as
(A) Tie (B) Degeneracy (C) Break (D) Shadow price
Ans: A
56. To solve degeneracy in the transportation problem we have to:
(A) Put allocation in one of the empty cells as zero
(B) Put a small element epsilon in any one of the empty cells
(C) Allocate the smallest element epsilon in such a cell, which will not form a closed loop with other loaded cells
(D) Allocate the smallest element epsilon in such a cell, which will form a closed loop with other loaded cells.
Ans: C
57. The cycle time, selected in balancing a line must be:
(A) Greater than the smallest time element given in the problem (B) Less than the highest time element given in the problem
(C) Slightly greater than the highest time element given in the problem (D) Left to the choice of the problem solver.
Ans: C
58. In queue designation A/B/S : (d/f), what does S represent?
(A) Arrival Pattern (B) Service Pattern
(C) Number of server (D) Capacity of the system.
Ans: C
59. In a control chart, the upper control limit is set equal to which one of the following?
(A) process mean (B) process mean plus three standard deviations
(C) upper design tolerance limit (D) upper value of the maximum range R.
Ans: B
60. Which one of the following best describes the situations for which the c chart is most suited?
(A) control of defective parts (B) mean value of part characteristic of interest
(C) number of defects in a sample (D) proportion of defects in a sample
Ans: C
61. A standard machine tool and an automatic machine tool are being compared for the production of a component. The following data refers to the two machines. Setup time, machining time and machine rate for standard machine tool are: 30 min, 22 min, and Rs. 200 per hour, and those for automatic machine tool are 2 hours, 5 min and Rs. 800 per hour, respectively. The break-even production batch size above which the automatic machine tool will be economical to use, will be
(A) 4 (B) 5 (C) 24 (D) 225
Ans: D
62. In a time study exercise, the time observed for an activity was 54 s. The operator had a performance rating of 120. A personal time allowance of 10% is given. The standard time for the activity, in seconds, is
(A) 54 (B) 60.8 (C) 72 (D) 58.32
Ans: C
63. Six sigma process has defect level below ______ defects per million opportunities.
(A) 3.4 (B) 4.5 (C) 5.6 (D) 6.7
Ans: A
64. The percent of the sample means will have values that are within ±3. Standard deviations of the distribution mean is
(A) 95.5 (B) 96.7 (C) 97.6 (D) 99.7
Ans: D
65. Gantt chart is mostly used for
(A) Routing (B) Scheduling (C) Follow up (D) Inspection and quality control
Ans: B
66. Match the following:
P. M05 1. Absolute coordinate system
Q. G01 2. Dwell
R. G04 3. Spindle stop
S. G90 4. Linear interpolation
(A) P-2, Q-3, R-4, S-1 (B) P-3, Q-4, R-1, S-2
(C) P-3, Q-4, R-2, S-1 (D) P-4, Q-3, R-2, S-1
Ans: C
67. The dimensional limits on a shaft of 25 h7 are
(A) 25.000, 25.021 mm (B) 25.000, 24.979 mm (C) 25.000, 25.007 mm (D) 25.000, 24.993 mm
Ans: B
68. An irreversible heat engine extracts heat from a high temperature source at a rate of 100 kW and rejects heat to a sink at a rate of 50 kW. The entire work output of the heat engine is used to drive a reversible heat pump operating between a set of independent isothermal heat reservoirs at 17°C and 75°C. The rate (in kW) at which the heat pump delivers heat to its high temperature sink is
(A) 50 (B) 250 (C) 300 (D) 360
Ans: C
69. Heat and work are
(A) intensive properties (B) extensive properties (C) point functions (D) path functions
Ans: D
70. A pump handling a liquid raises its pressure from 1 bar to 30 bar. Take the density of the liquid as 990 kg /m3. The isentropic specific work done by the pump in kJ/kg is
(A) 0.10 (B) 0.30 (C) 2.50 (D) 2.93
Ans: D
71. Which of the following is an intensive property of a system?
(A) pressure (B) mass (C) enthalpy (D) volume
Ans: A
72. A diesel engine is usually more efficient than a spark ignition engine because
(A) diesel being a heavier hydrocarbon, releases more heat per kg than gasoline
(B) the air standard efficiency of diesel cycle is higher than the Otto cycle, at a fixed compression ratio
(C) the compression ratio of a diesel engine is higher than that of an SI engine
(D) self-ignition temperature of diesel is higher than that of gasoline
Ans: C
73. The air–fuel ratio for idling speed of an automobile petrol engine is closer to
(A) 10:1 (B) 15:1 (C) 17:1 (D) 21:1
Ans: A
74. Allowance in limits and fits refers to
(A) maximum clearance between shaft and hole (B) minimum clearance between shaft and hole
(C) difference between maximum and minimum size of hole (D) difference between maximum and minimum size of shaft
Ans: B
75. A metal disc of 20 mm diameter is to be punched from a sheet of 2 mm thickness. The punch and the die clearance is 3%. The required punch diameter is
(A) 19.88 mm (B) 19.94 mm (C) 20.06 mm (D) 20.12 mm
Ans: A
76. In a steam nozzle, inlet pressure of superheated steam is 10 bar. The exit pressure is decreased from 3 bar to 1 bar. The discharge rate will
(A) remain constant
(B) decrease
(C) increase slightly
(D) increase or decrease depending on whether the nozzle is convergent or convergent divergent
Ans: A
77. In a steam nozzle, to increase the velocity of steam above sonic velocity by expanding steam below critical pressure
(A) a vacuum pump is added (B) ring diffusers are used
(C) divergent portion of the nozzle is necessary (D) abrupt change in cross-section is needed
Ans: C
78. In a steam condenser, the partial pressure of steam and air are 0.06 bar and 0.007 bar, respectively. The condenser pressure is
(A) 0.067 bar (B) 0.06 bar (C) 0.053 bar (D) 0.007 bar
Ans: A
79. The Rateau turbine belongs to the category of
(A) pressure compounded turbine (B) reaction turbine (C) velocity compounded turbine (D) radial flow turbine
Ans: A
80. The maximum blade efficiency of single stage impulse turbine in terms of nozzle angle α under ideal conditions is proportional to
(A) cos α (B) sin α (C) sin2 α (D) cos2 α
Ans: D
81. The degree of reaction of a turbine is the ratio of enthalpy drop in
(A) moving blades to enthalpy drop in the stage (B) fixed blades to enthalpy drop in the stage
(C) moving blades to enthalpy drop in fixed blades (D) fixed blades to enthalpy drop in moving blades
Ans: A
82. The degree of reaction of an impulse turbine:
(A) is less than zero (B) is greater than zero
(C) is equal to zero (D) increases with steam velocity at the inlet ___________________________
Ans: C
83. Which one of the following configurations has the highest fin effectiveness?
(A) Thin, closely spaced fins (B) Thin, widely spaced fins
(C) Thick, widely spaced fins (D) Thick, closed spaced fins
Ans: A
84. For an opaque surface, the absorptivity (α), transitivity (τ), and reflectivity (ρ) are related by the equation
(A) α+ρ = τ (B) α+ρ+τ = 0 (C) α+ρ = 1 (D) α+ρ = 0
Ans: C
85. The color of the flame of halide torch, in case of leakage of Freon refrigerant, will change to
(A) bright green (B) yellow (C) red (D) orange
Ans: A
86. The significant advantage of using ammonia as a refrigerant is its
(A) characteristic odor (B) high latent heat (C) solubility (D) inflammability
Ans: B
87. In a vapor compression refrigeration plant, the refrigerant leaves the evaporator at 195 kJ/kg and the condenser at 65 kJ/kg. For every kg of refrigerant, the plant can supply per second a cooling load of
(A) 70 kW (B) 100 kW (C) 130 kW (D) 160 Kw
Ans: C
88. Evaporative regulation of body temperature fails when the body temperature is
(A) more than wet bulb temperature but less than dry bulb temperature
(B) more than dew point temperature but less than wet bulb temperature
(C) more than dew point temperature but less than dry bulb temperature
(D) less than dew point temperature
Ans: D
89. The effective temperature is a measure of the combined effect of
(A) dry bulb temperature and relative humidity (B) dry bulb temperature and air motion
(C) wet bulb temperature and air motion (D) dry bulb temperature, relative humidity and air motion
Ans: D
90. In a Rankine cycle, regeneration results in higher efficiency because
(A) pressure inside the boiler increases (B) heat is added before steam enters the low pressure turbine
(C) average temperature of heat addition in the boiler increases (D) total work delivered by the turbine increases
Ans: C
91. Which of the following characteristics does not change during a reversible adiabatic process?
(A) Enthalpy (B) Internal energy (C) Rate of heat exchange (D) Entropy
Ans: D
92. Thermal diffusivity of a substance is:
(A) Proportional to thermal conductivity (B) Inversely Proportional to thermal conductivity
(C) Proportional to square of thermal conductivity (D) Inversely proportional square of thermal conductivity
Ans: A
93. The product of two complex numbers 1 +i and 2-5i is
(A) 7-3i (B) 3-4i (C) -3-4i (D) 7+3i
Ans: A
94. A rotameter is used to measure
(A) Rotational speed of a shaft (B) Kinetic energy of bodies in motion
(C) Flow of liquids (D) Twist produced in a shaft subjected to torque
Ans: C
95. The efficiency of a simple gas turbine can be improved by using a regenerator, because the
(A) Work of compression is reduced (B) Heat required to be supplied is reduced
(C) Work output of the turbine is increased (D) Heat rejected is increased
Ans: B
96. In a petro engine, the tendency of detonation increases with
(A) Retarded spark timings (B) Running the engine at high speeds (C) Supercharging (D) Increasing the cooling rate
Ans: C
97. A condenser of a refrigeration system rejects heat at rate of 120KW, while its compressor consumes a power of 30 KW. The coefficient of performance of the system would be
(A) 1 /4
(B)1 /3
(C) 3
(D) 4
Ans: C
98. What is the shape of the shearing stress distribution across a rectangular cross-section beam
(A) Triangular (B) Parabolic only (C) Rectangular only (D) A combination of rectangular and parabolic shape
Ans: B
99. Two like parallel forces are acting at a distance of 24 mm apart and their resultant is 20 N. If the line of action of the resultant is 6 mm from any given force, the two forces are
(A) 15 N and 5 N (B) 20 N and 5 N (C) 15 And 15 N (D) none of these
Ans: A
100. Inversion of a mechanism is
(A) Changing of a higher pair to lower pair (B) Obtained by fixing different links in a kinematic chain
(C) Turning it upside down (D) Obtained by reversing the input and output motion
Ans: B
Arc welding (AW)
Milling (M)
Drilling (D)
Punching of sheet metal (P)
Laser cutting of sheet metal (LC)
Spot welding (SW)
(A) AW, LC and M
(B) AW, D, LC and M
(C) D, LC, P and SW
(D) D, LC and SW
Ans: A
52. A shell of 100 mm diameter and 100 mm height with the corner radius of 0.4 mm is to be produced by cup drawing. The required blank diameter is
(A) 118 mm (B) 161 mm (C) 224 mm (D) 312 mm
Ans: C
53. In cold working,
(A) strength, hardness and ductility increase (B) strength and hardness increase, but ductility decreases
(C) strength, hardness and ductility decrease (D) strength and hardness decrease, but ductility increases
Ans: B
54. The word kanban is most closely associated with which one of the following?
(A) capacity planning (B) economic order quantity (C) just-in-time production (D) master production schedule
Ans: C
55. When the elements of net evaluation row of simplex table are equal, the situation is known as
(A) Tie (B) Degeneracy (C) Break (D) Shadow price
Ans: A
56. To solve degeneracy in the transportation problem we have to:
(A) Put allocation in one of the empty cells as zero
(B) Put a small element epsilon in any one of the empty cells
(C) Allocate the smallest element epsilon in such a cell, which will not form a closed loop with other loaded cells
(D) Allocate the smallest element epsilon in such a cell, which will form a closed loop with other loaded cells.
Ans: C
57. The cycle time, selected in balancing a line must be:
(A) Greater than the smallest time element given in the problem (B) Less than the highest time element given in the problem
(C) Slightly greater than the highest time element given in the problem (D) Left to the choice of the problem solver.
Ans: C
58. In queue designation A/B/S : (d/f), what does S represent?
(A) Arrival Pattern (B) Service Pattern
(C) Number of server (D) Capacity of the system.
Ans: C
59. In a control chart, the upper control limit is set equal to which one of the following?
(A) process mean (B) process mean plus three standard deviations
(C) upper design tolerance limit (D) upper value of the maximum range R.
Ans: B
60. Which one of the following best describes the situations for which the c chart is most suited?
(A) control of defective parts (B) mean value of part characteristic of interest
(C) number of defects in a sample (D) proportion of defects in a sample
Ans: C
61. A standard machine tool and an automatic machine tool are being compared for the production of a component. The following data refers to the two machines. Setup time, machining time and machine rate for standard machine tool are: 30 min, 22 min, and Rs. 200 per hour, and those for automatic machine tool are 2 hours, 5 min and Rs. 800 per hour, respectively. The break-even production batch size above which the automatic machine tool will be economical to use, will be
(A) 4 (B) 5 (C) 24 (D) 225
Ans: D
62. In a time study exercise, the time observed for an activity was 54 s. The operator had a performance rating of 120. A personal time allowance of 10% is given. The standard time for the activity, in seconds, is
(A) 54 (B) 60.8 (C) 72 (D) 58.32
Ans: C
63. Six sigma process has defect level below ______ defects per million opportunities.
(A) 3.4 (B) 4.5 (C) 5.6 (D) 6.7
Ans: A
64. The percent of the sample means will have values that are within ±3. Standard deviations of the distribution mean is
(A) 95.5 (B) 96.7 (C) 97.6 (D) 99.7
Ans: D
65. Gantt chart is mostly used for
(A) Routing (B) Scheduling (C) Follow up (D) Inspection and quality control
Ans: B
66. Match the following:
P. M05 1. Absolute coordinate system
Q. G01 2. Dwell
R. G04 3. Spindle stop
S. G90 4. Linear interpolation
(A) P-2, Q-3, R-4, S-1 (B) P-3, Q-4, R-1, S-2
(C) P-3, Q-4, R-2, S-1 (D) P-4, Q-3, R-2, S-1
Ans: C
67. The dimensional limits on a shaft of 25 h7 are
(A) 25.000, 25.021 mm (B) 25.000, 24.979 mm (C) 25.000, 25.007 mm (D) 25.000, 24.993 mm
Ans: B
68. An irreversible heat engine extracts heat from a high temperature source at a rate of 100 kW and rejects heat to a sink at a rate of 50 kW. The entire work output of the heat engine is used to drive a reversible heat pump operating between a set of independent isothermal heat reservoirs at 17°C and 75°C. The rate (in kW) at which the heat pump delivers heat to its high temperature sink is
(A) 50 (B) 250 (C) 300 (D) 360
Ans: C
69. Heat and work are
(A) intensive properties (B) extensive properties (C) point functions (D) path functions
Ans: D
70. A pump handling a liquid raises its pressure from 1 bar to 30 bar. Take the density of the liquid as 990 kg /m3. The isentropic specific work done by the pump in kJ/kg is
(A) 0.10 (B) 0.30 (C) 2.50 (D) 2.93
Ans: D
71. Which of the following is an intensive property of a system?
(A) pressure (B) mass (C) enthalpy (D) volume
Ans: A
72. A diesel engine is usually more efficient than a spark ignition engine because
(A) diesel being a heavier hydrocarbon, releases more heat per kg than gasoline
(B) the air standard efficiency of diesel cycle is higher than the Otto cycle, at a fixed compression ratio
(C) the compression ratio of a diesel engine is higher than that of an SI engine
(D) self-ignition temperature of diesel is higher than that of gasoline
Ans: C
73. The air–fuel ratio for idling speed of an automobile petrol engine is closer to
(A) 10:1 (B) 15:1 (C) 17:1 (D) 21:1
Ans: A
74. Allowance in limits and fits refers to
(A) maximum clearance between shaft and hole (B) minimum clearance between shaft and hole
(C) difference between maximum and minimum size of hole (D) difference between maximum and minimum size of shaft
Ans: B
75. A metal disc of 20 mm diameter is to be punched from a sheet of 2 mm thickness. The punch and the die clearance is 3%. The required punch diameter is
(A) 19.88 mm (B) 19.94 mm (C) 20.06 mm (D) 20.12 mm
Ans: A
76. In a steam nozzle, inlet pressure of superheated steam is 10 bar. The exit pressure is decreased from 3 bar to 1 bar. The discharge rate will
(A) remain constant
(B) decrease
(C) increase slightly
(D) increase or decrease depending on whether the nozzle is convergent or convergent divergent
Ans: A
77. In a steam nozzle, to increase the velocity of steam above sonic velocity by expanding steam below critical pressure
(A) a vacuum pump is added (B) ring diffusers are used
(C) divergent portion of the nozzle is necessary (D) abrupt change in cross-section is needed
Ans: C
78. In a steam condenser, the partial pressure of steam and air are 0.06 bar and 0.007 bar, respectively. The condenser pressure is
(A) 0.067 bar (B) 0.06 bar (C) 0.053 bar (D) 0.007 bar
Ans: A
79. The Rateau turbine belongs to the category of
(A) pressure compounded turbine (B) reaction turbine (C) velocity compounded turbine (D) radial flow turbine
Ans: A
80. The maximum blade efficiency of single stage impulse turbine in terms of nozzle angle α under ideal conditions is proportional to
(A) cos α (B) sin α (C) sin2 α (D) cos2 α
Ans: D
81. The degree of reaction of a turbine is the ratio of enthalpy drop in
(A) moving blades to enthalpy drop in the stage (B) fixed blades to enthalpy drop in the stage
(C) moving blades to enthalpy drop in fixed blades (D) fixed blades to enthalpy drop in moving blades
Ans: A
82. The degree of reaction of an impulse turbine:
(A) is less than zero (B) is greater than zero
(C) is equal to zero (D) increases with steam velocity at the inlet ___________________________
Ans: C
83. Which one of the following configurations has the highest fin effectiveness?
(A) Thin, closely spaced fins (B) Thin, widely spaced fins
(C) Thick, widely spaced fins (D) Thick, closed spaced fins
Ans: A
84. For an opaque surface, the absorptivity (α), transitivity (τ), and reflectivity (ρ) are related by the equation
(A) α+ρ = τ (B) α+ρ+τ = 0 (C) α+ρ = 1 (D) α+ρ = 0
Ans: C
85. The color of the flame of halide torch, in case of leakage of Freon refrigerant, will change to
(A) bright green (B) yellow (C) red (D) orange
Ans: A
86. The significant advantage of using ammonia as a refrigerant is its
(A) characteristic odor (B) high latent heat (C) solubility (D) inflammability
Ans: B
87. In a vapor compression refrigeration plant, the refrigerant leaves the evaporator at 195 kJ/kg and the condenser at 65 kJ/kg. For every kg of refrigerant, the plant can supply per second a cooling load of
(A) 70 kW (B) 100 kW (C) 130 kW (D) 160 Kw
Ans: C
88. Evaporative regulation of body temperature fails when the body temperature is
(A) more than wet bulb temperature but less than dry bulb temperature
(B) more than dew point temperature but less than wet bulb temperature
(C) more than dew point temperature but less than dry bulb temperature
(D) less than dew point temperature
Ans: D
89. The effective temperature is a measure of the combined effect of
(A) dry bulb temperature and relative humidity (B) dry bulb temperature and air motion
(C) wet bulb temperature and air motion (D) dry bulb temperature, relative humidity and air motion
Ans: D
90. In a Rankine cycle, regeneration results in higher efficiency because
(A) pressure inside the boiler increases (B) heat is added before steam enters the low pressure turbine
(C) average temperature of heat addition in the boiler increases (D) total work delivered by the turbine increases
Ans: C
91. Which of the following characteristics does not change during a reversible adiabatic process?
(A) Enthalpy (B) Internal energy (C) Rate of heat exchange (D) Entropy
Ans: D
92. Thermal diffusivity of a substance is:
(A) Proportional to thermal conductivity (B) Inversely Proportional to thermal conductivity
(C) Proportional to square of thermal conductivity (D) Inversely proportional square of thermal conductivity
Ans: A
93. The product of two complex numbers 1 +i and 2-5i is
(A) 7-3i (B) 3-4i (C) -3-4i (D) 7+3i
Ans: A
94. A rotameter is used to measure
(A) Rotational speed of a shaft (B) Kinetic energy of bodies in motion
(C) Flow of liquids (D) Twist produced in a shaft subjected to torque
Ans: C
95. The efficiency of a simple gas turbine can be improved by using a regenerator, because the
(A) Work of compression is reduced (B) Heat required to be supplied is reduced
(C) Work output of the turbine is increased (D) Heat rejected is increased
Ans: B
96. In a petro engine, the tendency of detonation increases with
(A) Retarded spark timings (B) Running the engine at high speeds (C) Supercharging (D) Increasing the cooling rate
Ans: C
97. A condenser of a refrigeration system rejects heat at rate of 120KW, while its compressor consumes a power of 30 KW. The coefficient of performance of the system would be
(A) 1 /4
(B)1 /3
(C) 3
(D) 4
Ans: C
98. What is the shape of the shearing stress distribution across a rectangular cross-section beam
(A) Triangular (B) Parabolic only (C) Rectangular only (D) A combination of rectangular and parabolic shape
Ans: B
99. Two like parallel forces are acting at a distance of 24 mm apart and their resultant is 20 N. If the line of action of the resultant is 6 mm from any given force, the two forces are
(A) 15 N and 5 N (B) 20 N and 5 N (C) 15 And 15 N (D) none of these
Ans: A
100. Inversion of a mechanism is
(A) Changing of a higher pair to lower pair (B) Obtained by fixing different links in a kinematic chain
(C) Turning it upside down (D) Obtained by reversing the input and output motion
Ans: B
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