Machine Design

51. If two springs are in parallel then their overall stiffness will be

  1. half
  2. same
  3. double
  4. unpredictable
  5. none of the above.

Correct answer: (C)
double

52. In composite or reverse laid ropes

  1. direction of twist of wires in strands is opposite to the direction of twist of strands
  2. direction of twist of wires and strands are same
  3. wires in two adjacent strands are twisted in opposite direction
  4. wires are not twisted
  5. none of the above.

Correct answer: (C)
wires in two adjacent strands are twisted in opposite direction

53. In cross or regular lay ropes

  1. direction of twist of wires in strands is opposite to the direction of twist of strands
  2. direction of twist of wires and strands are same
  3. wires in two adjacent strands are twisted in opposite direction
  4. wires are not twisted
  5. none of the above.

Correct answer: (A)
direction of twist of wires in strands is opposite to the direction of twist of strands

54. In hydrodynamic bearings

  1. the oil film pressure is generated only by the rotation of the journal
  2. the oil film is maintained by supplying oil under pressure
  3. do not require external supply of lubricant
  4. grease is used for lubrication
  5. none of the above.

Correct answer: (A)
the oil film pressure is generated only by the rotation of the journal

55. In hydrostatic bearings

  1. the Oil film pressure is generated only by the rotation of the journal
  2. the oil film is maintained by supplying oil under pressure
  3. do not require external supply of lubricant
  4. grease is used for lubrication
  5. none of the above.

Correct answer: (B)
the oil film is maintained by supplying oil under pressure

56. In most machine members, the damping capacity of the material should be

  1. low
  2. zero
  3. high
  4. could be anything
  5. none of the above.

Correct answer: (C)
high

57. In nitrated parts, the origins of the fatigue cracks will occur at

  1. surface
  2. just below the surface
  3. within the core
  4. could occur anywhere
  5. none of the above.

Correct answer: (E)
none of the above.

58. In oilness bearings

  1. the oil film pressure is generated only by the rotation of the journal
  2. the oil film is maintained by supplying oil under pressure
  3. do not require external supply of lubricant
  4. grease required to be applied after some intervals
  5. none of the above.

Correct answer: (C)
do not require external supply of lubricant

59. In order to avoid tearing of the plate at edge, the distance from the center line of the rivet hole to the nearest edge of the plate in terms of dia. of rivet d should be equal to

  1. d
  2. 1.25 d
  3. 1.5 d
  4. 1.75 d
  5. 2 d.

Correct answer: (C)
1.5 d

60. In order to obtain bolt of uniform strength

  1. increase shank diameter
  2. increase its length
  3. drill an axial hole through head up to threaded portion so that shank area is equal to root area of thread
  4. tighten die bolt properly
  5. all of the above.

Correct answer: (C)
drill an axial hole through head up to threaded portion so that shank area is equal to root area of thread

Page 6 of 14