1. The property of a material by virtue of which it can be beaten or rolled into plates is
called____
Malleability
2. It is defined as the stress developed in the material without any permanent set.
None of the listed
3. A load that is applied at some initial velocity.
Impact load
4. Modulus of rigidity is the ratio of
Shear stress and shear strain
5. Hooke’s law holds good up to
Elastic limit
6. What is the metal characteristic to withstand forces that cause twisting?
Torsional Strength
7. It is the ability of a material to be deformed considerably without rupture.
Plasticity
8. It is the property by virtue of which a material is deformed under the load and is
enabled to return to its original dimension when the load is removed.
Elasticity
9. The Young’s modulus for mild steel in GPa is approximately equal to ___.
210
10. Deformation per unit length in the direction of force is known as
linear strain
11. In AISI C1118, as rolled, how much carbon is present?
0.18%
12. The ratio of the ultimate stress or yield stress of a material to the design stress is
known as
factor of safety
13. If a material expands freely due to heating it will develop _
thermal stress
14. The value of Poisson's ratio for steel is between
0.25-0.33
15. The resistance of a material to indentation by a penetrator is an indication of its ___
Hardness
16. The maximum energy that can be stored in a body due to external loading up to the
elastic limit is called _
Strain energy
17. It is the energy stored by a body undergoing deformation.
Strain energy
18. What is the metal characteristic to withstand forces that cause twisting?
Torsional strength
19. Failure of a material is called fatigue when it fails
below the yield point
20. The ratio of linear stress to linear strain is called
modulus of elasticity
21. Compute the fatigue-strength reduction factor for a theoretical stress concentration
factor of 1.62 and notch sensitivity of 0.9.
1.558
22. When a hole of diameter ‘d’ is punched in a metal of thickness `t’, then the force
required to punch a hole is equal to ___.
πdtSu
23. The Modulus of Elasticity for Shear for mild steel is approximately __
80 GPa
24. Which failure criterion is applicable when failure criterion is not assumed and the
mean stress and alternating stress are non-zero?
Goodman
25. Which pressure vessel is strongest?
Spherical vessel
26. The stress in the bar when load is applied suddenly is ___ as compared to the stress
induced due to gradually applied load.
Double
27. In torsion, the maximum stress happens at
outermost fiber
28. When a material is subjected to fatigue loading, the ratio of its ultimate tensile
strength to its endurance limit is __
-0.5-
29.
A pressure vessel is said to be a thick cylindrical shell, if the ratio of the wall
thickness of the shell to its diameter is
none in the list
30. The endurance or fatigue strength may be defined as the maximum safe stress which
can be applied to a machine member under_
Variable conditions
31. If the size of a standard specimen for a fatigue testing machine is increased, the
endurance strength of the material will ___.
Decrease
32. The longitudinal stress is ___ of the circumferential stress.
One-half
33. This type of thread is common in mechanical jack
square thread
34. The common type of thread for bench vise is
Buttress
35. Which form of thread has an included angle between the flanks of thread of 29
degrees?
ACME Thread
36. The endurance or fatigue limit is defined as the maximum value of the stress which a
polished standard specimen can withstand without failure, for infinite number of
cycles, when subjected to
completely reversed load
37. The design of the thin-walled pressure vessel is based on ___.
*longitudinal and girth stresses
38. The root diameter of a double square thread is 0.55 in. The screw has a pitch of 0.20
in. Find the number of threads per inch.
5
39. Which of the following cannot be measured directly by precision instruments?
Pitch diameter
40. When helical compression spring is cut into quarters, the stiffness of the resulting
spring will be
Quadruple
41. What form of thread is suitable for lead screws of machine tools?
ACME thread
42. This type of threads is suitable for small precision components and measuring gauges.
BA thread
43. Line joining Sy (yield strength of the material) on mean stress axis and Sn’
(endurance limit of the component) on stress amplitude axis is called as _.
Soderberg line
44. When a helical compression spring is subjected to an axial compressive load, the
stress induced in the wire is ___.
none in the list
45. The shaft directly connected to the power source is called a
Line shaft
46. The effect of stress raiser in compression is __.
Zero
47. For a solid circular cross-section, the radius of gyration is___.
d/4
48. A connecting rod is considered like __ for buckling about Y-axis.
both ends fixed
49. Common application of Eye bolts is in
absorbing shocks and vibrations
50. It is a cylindrical rod having a head at one end and fitted with a nut at the other end
Tap bolt
51. Wahl’s factor is related to the spring index, such that it ___, as the spring index
decreases.
Increases very rapidly
52. The angle of twist of shaft is inversely proportional to (shaft diameter)
4
53. It is a cylindrical rod having a head at one end and fitted with a nut at the other end
imaginary
54. A saddle key __ power through frictional resistance only.
Transmits
55. It is a key that is tapered and fits in a keyway in the hub and is flat on the shaft.
Flat saddle key
56. The inclined member carrying compressive loads is __.
Strut
57. A mild steel rod of 12 mm diameter was tested for tensile strength with the gauge
length of 60 mm. After the test the final length and the final diameter were 80 mm and
7 mm, respectively. Find the strain in the transverse direction.
0.417
58. The buckling load will be maximum for a column, if
Both ends of the column are clamped
59. The direct stress induced in a long column is………….. as compared to bending
stress.
Negligible
60. A kind of thread in which the width of the thread is approximately equal to its depth
and the space between the threads is uniform
Square thread
61. The root diameter of a triple square thread is 0.65 in. The screw has a pitch of 0.2 in.
Find the lead.
0.6
62. Which is correct for hollow saddle key?
A taper key which fits in a key way of the hub and the bottom of the key is shaped to
fit the curved surface of the shaft
63. This form of screw thread is a modification of square thread and has rounded top and
bottom
American
64. It is the slanted distance between the crest and the root of a single-start thread.
Flank
65. Which of the following thread is not used for power transmission in either direction?
BSW thread
66. Two plates 50 mm wide and 20 mm thick are lap jointed by a 20-mm dia. pin and
loaded with 75 kN tensile force. Estimate shear stress on the pin in MPa.
239
67. This type of sunk key having uniform cross section throughout and taperless is used
where the pulley, gear or other mating piece is required to slide along the shaft
parallel sunk
68. A screw is said to be self -locking screw, if its efficiency is ___
less than 50%
69. It is the distance measured normal to the bolt axis which is the shortest straight
distance between the crest and the root of a single thread.
depth of thread
70. Two shafts A and B of solid circular cross-section are identical except for their
diameters dA and dB. The ratio of power transmitted by the shaft A to that of shaft B
is ___.
(dA)3/ (dB)3
71. 100-mm diameter shaft with Modulus of Elasticity for shear of 83 GPa is subjected to
a torque of 5000 N-m. What is the allowable angle of twist per meter length?
0.006
72. Which of the following statements is true?
Shafts transmit power while axles do not transmit power.
73. shafts A and B are made of the same material. If he diameter of shaft A is two-thirds
as that of shaft B, find the ratio of the power transmitted by shaft A to that of shaft B.
0.3
74. A seamless cylinder of storage capacity of 0.03m3 is subjected to an internal pressure
of 21 MPa. The allowable stress in the material of cylinder is 350N/mm².Determine
the length of the cylinder if it is twice the diameter of the cylinder.
8mm
75. Calculate the impact load induced by a 10-lb free falling rigid body on a 12-in long
vertical bar fixed at the bottom. The bar has a diameter of one inch and is made of
steel. The free falling body, which is at an initial height of 5 in. is to hit the top of the
bar upon impact.
14022
76. A cantilever timber beam of 4-m span carries a concentrated load W at the free end.
The cross-section of the beam is 150-mm wide and 250-mm deep. Find the
permissible value of W if the allowable working stress is 7 MPa.
2734 N
77. A seamless cylinder of storage capacity of 0.03mᵌis subjected to an internal pressure
of 21MPa. The ultimate strength of material of cylinder is 350N/mm².Determine the
length of the cylinder if it is twice the diameter of the cylinder.
540mm
78. A spherical air tank stores air at 3000 psig. The tank is to have an inside diameter of 7
in. What should be the wall thickness of the tank if it is made of AISI 301, ¼-hard
stainless steel (Sy = 75 ksi), with a design factor of 1.5 based on the yield strength and
a joint efficiency of 90%.
0.1167
79. Determine the bursting steam pressure of a steel shell with diameter of 10 inches and
made 1/4 in thick steel plate. The joint efficiency is 70%and the tensile strength is 60
ksi.
4200 psi
80. A machine member made of brittle material is subjected to varying torsional loads
where the alternating stress is 34000 psi. The material’s endurance strength and the
mean stress can be taken as 85 ksi and 42.5 ksi, respectively. For a factor of safety
based on Goodman criterion of 1.8, estimate the ultimate strength of the material in
psi.
273214
81. Two shafts of the same length and material are joined in series. If the ratio of their
diameters is two, then the ratio of their angles of twist will be ___.
16
82. A steel shaft of 50 mm diameter and 500 mm length has a total angle of twist of 0.5. If
the Modulus of Rigidity is taken as 79 GPa, determine the maximum allowable shear
stress that can be induced in the shaft.
34.5 Mpa
83. A 25-mm hole is punched on a 20-mm thick plate with a vertical force of 27067 lbf.
Find the punching shear stress in MPa.
76.7
84.
90.
1. The irregularity in the stress distribution is caused by abrupt changes of form which
include any discontinuity or change in cross-section of a machine member, such as
scratches. These abrupt changes are known as __.
a) Stress raisers
b) Localized stresses
c) Stress reducers
d) Stress concentrations
2. What is the stress to strain ratio within the elastic limit?
a) Modulus of elasticity
b) Compressive ratio
c) Elastic limit
d) Elasticity
3. In AISI C1045, as rolled steel, what is the percent carbon?
a) 0.50%
b) 0.10%
c) 0.40%
d) 0.45%
4. A keyseat lowers __.
a) The ductility of the shaft
b) The rigidity of the shaft
c) The strength of the shaft
d) Both the strength and rigidity of the shaft
5. Stress concentration is caused due to ___.
a) Pitting at points or areas at which loads on a member are applied
b) All in the list
c) Variation in properties of material from point to point in a member
d) Abrupt change of section
6. Pitch diameter of a screw thread is ____.
a) Imaginary diameter
b) Nominal diameter
c) Maximum diameter
d) Minimum diameter
7. For power screw, which is correct?
a) Efficiency of ACME thread is less than that of Square thread
b) Efficiency of self-locking screw cannot be more than 50%
c) If friction angle is greater than the lead angle of the screw, the efficiency will be
more than 50%
d) All in the list
8. When two helical springs of equal lengths are arranged to form a cluster spring, then
___.
a) Deflection of each spring is identical
b) All in the list
c) Load carried by one spring is one-half of the total load
d) Shear stress on each spring is the same
9. What is the length of the key, L to diameter of the shaft, d ratio when the materials for
both shaft and key are identical?
a) �/4****
b) �/2
c) None in the list
d) �
10. A solid circular shaft is subjected to combination of bending moment “M” and
twisting moment “T”. If the maximum bending stress equals the maximum shear
stress developed, then “M” is equal to ___.
a) 2T
b) 4T
c) T/2
d) T