SHAFTING, KEYS AND SPLINES, COUPLINGS

1. Compute for the polar section modulus of a Monel shafting having a diameter of 4 inches. Use a
factor of safety of 5 and design stress at 1000 kPa.

A. 4.7 B. 12.56 C. 4.2 D. 5.3

2. The torsional capacity of a spline fitting is based on the maximum allowable pressure on the
active surface of the splines. The major diameter of the spline fitting is 75 mm, and minor diameter
of 60 mm. It has 6 splines and a coefficient of friction of 0.10. Considering the pressure in the active
surface of 7 MPa, determine the length of the spline needed for a transmitted torque of 750 N-m.

A. 54.70mm B. 70.54mm C. 65.40mm D. 83.29mm

3. The shaft is subjected to a steady load of 36,000 lbs at a shear stress of 10,000 psi. Compute the
diameter of the said shaft in inches.

A. 1 ⅞ B. 2 ¼ C. 3 D. 2 ¾

4. A stepped torsion shaft has diameters of 16 mm and 12 mm and a fillet radius of 2mm. The shaft
is subjected to a torque of 12.5 N-m. Find the maximum induced stress caused by the fillet.
Consider a stress concentration factor of 1.25

A. 36.84 MPa B. 46.05 MPa C. 38.64 MPa D. 45.06 MPa

5. A hollow shaft has an outside diameter of 4-in and an inside diameter of 3-in. Find the diameter
of a solid shaft with equal strength in torsion.

A. 2.52 in B. 1.52 in C. 4.52 in D. 3.52 in

6. A model 108 spline connection, 8 x 52 x 60 is used for gear and shaft. The coefficient of friction is
0.06, rotating at 120 RPM with transmitted power of 20 kW and a normal pressure of 6.5 MPa. What
is the force needed for shifting?

A. 3.41 kN B. 2.75 kN C. 2s0.12 kN D. 5.12 kN

7. A small countershaft is 1 ½ inch in diameter and has an allowable stress of 58.59 MPa. Find the
power delivered by the shaft at a speed of 150 RPM.

A. 13.13 kW B. 1.4 HP C. 9.93kW D. 14.72 HP

8. What is the outside diameter of a hollow shaft replacing a 150 mm diameter solid shaft with
equal torsional strength and 50% weight saved?

A. 180mm B. 190mm C. 160mm D. 170mm

9. A Model 108 spline connection, 8 x 52 x 60 is used for gear and shaft. The coefficient of friction is
0.06, rotating at 120 RPM with transmitted power of 20 kW and a normal pressure of 6.5MPa. What
is the torque transmitted?

A. 1.982 kN-m B. 1.592 kN-m C. 1.092 kN-m D. 3.298 kN-m

10. A 3 in diameter short shaft carrying pulleys close to the bearings transmit how much
horsepower if the shaft makes 280 rpm?

A. 991 hp B. 919 hp C. 199 hp D. 260 hp

11. A solid circular steel column with hinged ends is 900-mm long 70 mm. in diameter. Yield point
stress of material is 350 MPa. Find the moment of inertia of the solid circular steel column.

A. 𝟏𝟏𝟖 𝒄𝒎𝟒 B. 100 𝑐𝑚4 C. 72 𝑐𝑚4 D. 59 𝑐𝑚4

12. A solid circular shaft needs to be designed to transmit a torque of 50 N-m. If the allowable shear
stress of the material is 140 MPa, assuming a factor of safety of 2, the minimum allowable design
diameter is mm is,

A. 8 B. 16 C. 24 D. 3

13. The torsional capacity of the spline fitting is based on the maximum allowable pressure on the
active surface of the splines. The major diameter of the spline fitting is 75 mm, and minor diameter
of 60 mm. It has 6 splines and a coefficient of of friction of 0.10. Considering the pressure in the
active surface to be 7MPa, determine the force required to slide the splines axially under load for a
transmitted torque of 750 N-m.

A. 6.58 lbs B. 499 lbs C. 2.22 lbs D. 7.5 kN

14. A 1 inch diameter shaft has a 2 in diameter collar resting on a support. The axial load on the
shaft is 10,000 lb and the thickness of the collar is ½ in. How much sharing stress is induced?

A. 6366.20 psi B. 4234.56 psi C. 5244.56 psi D. 8456.34 psi

15. What is the actual hole diameter made by a steel of 19 mm that is subjected to a 178 kN
hydraulic press?

A. 19.34 mm B. 1.91 cm C. 0.75068 mm D. 2.58 mm

16. A standard splined connection 8 x 52 x 60 mm is used for the gear and shaft assembly of
gearbox. The splines transmit 20 kW power at 300 RPM. The permissible normal pressure on the
splines is 6.5 MPa with the coefficient of friction of 0.06. Compute the mean radius.

A. 28 mm B. 8 mm C. 52 mm D. 30 mm

17. A ⅛-in diameter round steel shaft was designed for a torsional stress of 8000 psi. If it rotates at
2000 rpm, what horsepower can it transmit?

A. 0.0974 HP B. 0.0674 HP C. 0.774 HP D. 0.0874 HP

18. A standard splined connection 6 x 52 x 60 mm is used for the gear and shaft assembly of
gearbox. The splines transmit 30 HP power at 300 RPM. The permissible normal pressure on the
splines is 7.6 MPa with coefficient of friction of 0.06. Estimate the no. of splines

A. 7 B. 8 C. 6 D. 10
19. A steel shaft 1.75 inches in diameter transmits 40 Hp at 1800 rpm. Assuming a modulus of
rigidity of 12 × 106 psi, find the torsional deflection of the shaft in degrees per foot length.

A. 0.0073 B. 0.0674 HP C. 0.774 HP D. 0.0874 HP

20. An 80-mm solid shaft is to be replaced with a hollow shaft of equal torsional strength. Find the
percentage of weight saved, if the outside of the hollow shaft is is 100 mm.

A. 56.53% B. 67.31% C. 48.49% D. 52.90%

21. A flange coupling is to be designed, using 25 mm diameter bolts at a distance of 152 mm from
the center of the shaft allowable shearing stress on the bolt is 103 MPa. If the shaft is to transmit
5,600 hp at a speed of 1200 rpm, how many bolts are needed in the connection?

A. 2 B. 3 C. 4 D. 5

22. A 2.5-in diameter shaft uses a straight spline with six splines and a contact length of 1.25 in.
Assuming it is designed to slide while under load, compute its torque transmission capacity at 100
RPM if h=0.10D.

A. 2,109 in-lb B. 1,425 in-lb C. 3,450 in-lb D. 6523.23 in-lb

23. A model 108 spline connection, 8 x 52 x 60 is used for gear and shaft. The coefficient of friction
is 0.06, rotating at 120 RPM with transmitted power of 20 kW and a normal pressure of 6.5 MPa.
What is the normal force?

A. 90.28 kN B. 56.86 kN C. 12.73 kN D. 78.37 kN

24. A standard splined connection 10 x 50 x 56 mm is used for the gear and shaft assembly of
gearbox. The splines transmit 20 kW power at 300 RPM. The permissible normal pressure on the
splines is 6.5 MPa with the coefficient of friction of 0.06. Compute for the mean diameter.

A. 28 B. 8 C. 53 mm D. 30

25. The equivalent bending moment of a shaft under torque of 5,000 in-lb and a bending moment of
8,000 in-lb, ang having a diameter of 2 inches is

A. 8717 B. 9434 C. 8,000 D. 5,000

26. A keyed sprocket delivers a torque of 778.8 N-m thru the shaft of 54 mm OD. The key thickness
is 1.5875 cm and the width is 1.11 cm. Compute the length of the same key. The permissible stress
value of 60 MPa for shear and 90 MPa for tension.

A. 39.12 cm B. 4.82 cm C. 52.22 cm D. 4.32 cm

27. Find the inside diameter of a hollow shaft which will replace a 3-in solid shaft made of the same
material, hollow shaft should be equally strong in torsion, yet weigh half as much per foot.

A. 3.21 in B. 2.34 in C. 2.94 in D. 3.62 in

28. A 1-in solid shaft is to be replaced with a hollow shaft equal torsional strength having an outside
diameter of 2-in, how much is the percentage of weight saved?
A. 37% B.66% C. 57% D. 74%

29. A flexible shaft consists of a 5-mm diameter steel wire encased in stationary tube that fits
closely enough to impose a frictional torque of 2 N.m/m. If the shearing stress is not exceed 140
MPa, what will be the angular rotation of one end relative to the other end? Use G = 83 GPa

A. 32.06 deg B. 34 deg C. 33.21 deg D. 31.21 deg

30. What is the actual hole diameter made by a steel of 0.75-inch diameter that is subjected to a
40,000 pounds Hydraulic press?

A. 5.32 m B. 0.96 m C. 0.75068 in D. 3.809 cm

31. A line shaft with a power of 150 kW at a speed of 1200 rpm, had a rectangular key used in its
pulley connection. Consider the shearing of stress of the shaft to be 40 MPa and the key to be 200
MPa, determine the shaft diameter

A. 66.622 mm B. 53.31 mm C. 40.82 mm D. 44.94 mm

32. The equivalent twisting moment of a shaft under torque of 6,000 in-lb and a bending moment of
9,000 in-lb, ang having a diameter of 5 inches is

A. 2182 B. 1873 C. 7382 D. 10,816

33. A 2-in shaft is supported by bearings 90 inches apart. The shaft carries no rotating discs and is
assumed to weigh 0.28 lb/in, have a modulus of elasticity of 30,000,000 psi, and have a uniform
cross section (round), Find the lowest critical speed

A. 1055 rpm B. 4220 rpm C. 2100 rpm D. 6330 rpm

34. A model 108 spline connection, 8 x 52 x 60 is used for gear and shaft. The coefficient of friction
is 0.06, rotating at 120 RPM with transmitted power of 20 kW and a normal pressure of 6.5 MPa.
What is the normal length of the hub?

A. 273 cm B. 90 cm C. 10.75 in D. 237 mm

35. A 250 hp motor turns a shaft at 2400 rpm. The shaft steps down in diameter from 3.0 to 2.5
inches. Calculate the maximum torsional shear stress if the stress concentration factor is given to
be 1.32

A. 19.2 MPa B. 22.5 MPa C. 17.5 MPa D. 19.49 MPa

36. A step shaft made of SAE 1117 steel with an ultimate strength of 69.7 ksi. The notch sensitivity
factor is 0.983 and the constant dependent upon the ultimate strength is 0.00435, check the radius
stress raiser.

A. 0.192 B. 0.386 C. 0.250 D. 0.775

37. A 25 mm shaft is keyed to a 300 mm diameter pulley and transmits 3 KW of power. The keyed
assembly rotates at 1725 rpm. What is the tangential force at the key?

A. 1.33 KN B. 5.23 KN C. 2.33 KN D. 8.34 KN

38. A 1.5 diameter 10-spline shaft (d = 0.91D, w = 0.156D, h = 0.045D) and permanent fir has a
compressive force of 2200 lbs. Find the torque applied if hub length is 1.75 in.

A. 20 N-m B. 12 N-m C. 24 N-m D. 34 N-m

39. A metric M4 x 15 square key is used with a 16 mm shaft. If the allowable shearing stress is 50
MPa. How much torque can the assembly handle? The rotational speed of the shaft is 600 rpm.

A. 20 N-m B. 12 N-m C. 24 N-m D. 34 N-m

40. A flat key is to be designed for a 75 mm diameter shaft which will transmit 150 KW at 400 rpm. If
allowable shearing stress is 200 Mpa and key width is 15 mm, determine the length of key.

A. 30.65 mm B. 31.83 mm C. 33.75 mm D. 32.85 mm

41. A step shaft made of SAE 1117 steel with an ultimate strength of 480 MPa. The radius stress
raiser is 0.30 and the constant dependent upon the ultimate strength is 0.00435, what is the notch
sensitivity factor?

A. 0.25 B. 0.983 C. 0.986 D. 0.391

42. A rectangular key is used in pulley to transmit 100 Kw at 1000 rpm on 50 mm shaft diameter.
Determine the force required to remove the shaft from the hub of friction is 0.4

A. 33.24 KN B. 36.85 KN C. 28.35 KN D. 30.55 KN

43. A 1 ½ -in diameter torsion shaft has a groove radius of ¼ -in.The shaft diameter at the groove is 1
in. The shaft is made of cold-drawn Monel with ultimate tensile stress of 100 ksi. Find the design
stress for a factor of safety of 8, assuming stress of Monel is ⅝ of the ultimate tensile stress, and
the stress concentration is 1.48?

A. 12,500 psi B. 18,500 psi C. 11,560 psi D. 42,230 psi

44. A pulley is keyed to a 24 mm steel shaft with a metric M6 x 20 square key. If the hub length is 20
mm and the allowable shearing stress for the key material is 100 MPa, how much torque can be
transmitted?

A. 0.133 kN-m B. 0.155 kN-m C. 0,144 kN-m D. 0.166 kN-m

45. A flange bolt coupling consists of eight steel 20 mm diameter bolts spaced evenly around a bolt
circle 300 mm in diameter. If the coupling is subjected to a torque of 15.1 KN-m, determine the
maximum shearing stress in the bolts?

A. 40450 kPa B. 63320 kPa C. 40054 kPa D. 31298 kPa

46. A 2 inches diameter 6-spline shaft (d = 0.90D, w = 0.25D, h = 0.25D) and permanent fit has a
compressive force of 2000 lbs. Find the compressive stress if hub length is 1 ½ in.

A. 450.00 psi B. 445.00 psi C. 500.00 psi D. 400.00 psi

47. The maximum shear stress induced on a 1.5’’ diameter solid loaded with a torque of 8,000 in-lb
and a bending moment of of 12,000 in-lb is
A. 21,760 psi B. 62,237 psi C. 27,220 psi D. 14,422 psi

48. A flexible shaft consists of 5-mm diameter steel wire encased in stationary tube that fits closely
enough to impose a frictional torque of 2 N.m/m. Determine the maximum length of the shaft if the
shearing stress is not to exceed 140 MPa.

A. 1.817 m B. 3.289 m C. 1.718 m D. 2.17 m

49. A flanged coupling is designed to use 6 bolts on a 4-in diameter bolt circle. The allowable stress
in shear 12,000 psi; the maximum torqued is 50 ft-lbf. Find the diameter of the bolt required

A. 1.85 mm B. 1.52 mm C. 0.073 mm D. 3.2 mm

50. A hollow shaft with outside diameter of 4.5 in, and a wall thickness of ¼ in. transmits 275 hp at
390 rpm. Calculate the shear stress at the inner diameter of the shaft

A. 6611.0 psi B. 5876.5 psi C. 6116.0 psi D. 5544.0 psi

51. Which of the following can be calculated indirectly using the properties of Density and velocity
of sound in the material?

A. Shear Modulus C. Modulus of rigidity

B. Modulus of elasticity D. Bulk modulus

52. A thin homogeneous metallic plate containing a hole is heated sufficiently to cause expansion.
If the coefficient of surface expansion is linear, the are of the hole will:

A. Increase at twice the rate the area of the metal increases

B. Increase at the same rate as the area of the metal increases

C. Decrease at twice the rate as the area of the metal increases

D. Decrease at the same rate as the area of the metal increases

53. How do you call the speed at which a rotating shaft becomes dynamically unstable?

A. Normal Speed C. Critical speed

B. Variable speed D. Average speed

54. A type of key in which width and thickness are equal is called as:

A. Flat key B. Square key C. Pin key D. Barth key

55. How do you call the ratio of lateral strain to longitudinal strain?

A. Poisson’s ratio C. Modulus of rigidity

B. Modulus of resilience D. Offset ratio

56. A universal coupling is

A. Flexible coupling C. used to connect perfectly aligned shafts

B. Rigid coupling D. None of these

57. A feather key is usually

A. Tight in shaft and loose in hub C. loose in shaft and loose in hub

B. loose in shaft and tight in hub D. tight in shaft and tight in hub

58. A key that transmits power through frictional resistance only is;

A. sunk key B. saddle key C. tangent key D. round key

59. Number of critical speed for any shaft is:

A. one B. two C. infinite D. size

60. A piece of mild steel inserted between the shaft and hub to connect them together, is known as

A. rivet B. bolt C. key D. none of these

61. A transmission shaft subjected to bending loads must be designed on the basis of

A. maximum normal stress theory

B. maximum shear stress theory

C. maximum normal stress and maximum shear stress theories

D. fatigue strength

62. Which sunk key made the form of a segment of a circular disc of uniform thickness, known as?

A. Feather key B. Kennedy key C. Woodruff key D. Saddle key

63. An axle is a machine part that is subjected to

A. Transverse loads and bending moment C. Twisting moment and axial load

B. Twisting moment only D. Bending moment and axial load

64. What type of key that allows the hub to move along the shaft but prevents the rotation of the
shaft?

A. Woodruff key B. Feather key C. Gibbs key D. Square key

65. A sunk key is provided with a gib head

A. to fit easily C. to transmit shock

B. to remove easily D. all of these

66. In designing a shaft, hub and key for a system, weakest member taken is

A. shaft B. hub C. key D. all are equally s

67. What is the other name for Kenny key?

A. tangential key B. woodruff key C. saddle key D. roll pin

68. Holding power of a sunk key is due to resistance, which it offers in

A. shear C. crushing

B. shear and crushing D. tension and shear

69. A flange coupling is:

A. used for collinear shaft C. rigid coupling

B. used for non-collinear shafts D. flexible

70. A coupling used for absorbing some shock and vibration that may appear on one shaft and of
preventing the occurrence of reversed stresses caused by the shaft by the shaft deflecting at the
coupling preventing at the coupling

A. rigid coupling B. flange coupling C. flexible coupling D. None of these

71. The speed at which the center of mass will be equal the deflecting forces on the shaft; the shaft
with its attached bodies will then vibrate violently since the centrifugal force changes its direction
as the shaft trunks in:

A. nominal speed B. critical speed C. relative speed D. mean speed

72. Which type of key is used for mounting shifting gears in gear boxes?

A. splines B. saddle C. square D. flat

73. Splines are used when:

A. the power transmitted is low

B. the power to be transmitted is high

C. axial relative motion between shafts and hub is necessary

D. flame hardening

74. Which of the following will best describe the sunk key?

A. the key is helical along shaft C. the keyway is cut in shaft only

B. the keyway is cut in hub only D. the key is cut in both shaft and hub

75. Commonly utilized/cheapest shaft material available in the market with carbon content of 0.28
to 0.34%

A. SAE 4132 B. SAE 4320 C. SAE 1030 D. SAE 4130

76. When the hole is smaller than the shaft, it will take pressure to put the parts together. The
allowance is said to be negative and its termed.

A. negative tolerance C. negative fits

B. negative allowance D. interference of metal

77. Axially located rectangular groove in a hub and shaft

A. keyseat B. cotter pin set C. flute D. setscrew point

78. What is the rotating member used in transmitting power?

A. shaft B. counter shaft C. axle D. washer

79. For machinery shafts, the permissible deflection is approximately:

A. 0.02 in./ft B. 0.03 in//ft C. 0.01 in./ft D. 0.05 in./ft

80. For shafts, the shear due to bending is a maximum at the neutral plane where the normal stress
is:

A. minimum B. constant C. maximum also D. zero

81. Stress concentration is caused due to

A. variation in properties of material from point to point in a member

B. pitting at points or areas at which loads on a member are applied

C. abrupt change of section

D. all of the above

82. Which of the following is not correct procedure to increase the fatigue limit

A. cold working C. surface decarburisation

B. shot peening D. under-stressing

83. A key capable of tilting in a recess milled out in a shaft is known as

A. wood-ruff key B. feather key C. flat saddle key D. gib head key

84. A key made from a cylindrical disc having segmental cross-section, is known as

A. wood-ruff key B. feather key C. flat saddle key D. gib head key

85. A tapered key which fits in a key-way in hub and is flat on the shaft, is known as

A. wood-ruff key B. feather key C. flat saddle key D. gib head key

86. Which of the following key is preferred for the both condition when a large amount of impact
type torque is to be transmitted in both direction of rotation?

A. woodruff key B. feather key C. gib head key D. tangent key

87. The maximum strain energy that can be stored in a body is known as

A. impact energy B. resilience C. proof of resilience D. modulus

88. Feather keys are generally

A. tight in shaft and loose in hub C. tight in both shaft and hub

B. loose in shaft and tight in hub D. loose in both/shaft and hub

89. The distribution of stress along the length of a key fitted in shaft

A. is uniformly constant

B. varies linearly

C. is of exponential shape, being more at the torque input end

D. is of exponential shape, being less at the torque input end

90. Which of the following steel key is usually strong in failure by shear and crushing

A. rectangular B. flat C.square D. circular

91. A saddle key

A. is provided in the hub only and hollowed to fit the shaft

B. has flat surface and the shaft is planned off to accommodate the key

C. is fitted such that each withstands torsion in one direction only

D. is designed to fit in a sunk key-way whose bed is parallel to the axis of shaft

92. Stress concentration is cyclic loading is more serious in

A. Ductile materials C. Equally serious in both cases

B. Brittle materials D. Depends on other factors

93. While transmitting the same power by a shaft, if its speed is doubled, what should be its new
diameter if the maximum shear stress induced in the shaft remains the same?

A. ½ of the original diameter

B. 1/sqrt 2 of the original diameter

C. sqrt 2 of the original diameter

D. 1/cu. rt of 2 of the original diameter

94. Two shafts, one of solid section and the other of hollow section, of same material and weight
having same length are subjected to equal torsional force. What is the torsional stiffness of hollow
shaft

A. equal to that of the solid shaft C. more than that of the solid shaft

B. less than that of the solid shaft D. exactly half of that of the solid shaft

95. The speed rating for turbine rotors is invariably more than sqrt 2 times its natural frequency to
A. increase stability under heavy load and high speed

B. isolate vibration of the system from the surrounding

C. minimize deflection under dynamic loading as well as to reduce transmissibility of force to the
surrounding

D. none of the above

96. The accurate method of finding the natural frequency of transverse vibrations of a system of
several loads attached to some shaft is

A. dunkerley method C. stodola method

B. energy method D. dunkerley and energy method

97. Rayleigh’s method of computing the fundamental natural frequency is based on

A. conservation of energy C. conservation of masses

B. conservation of momentum D. laws of statics

98. Which one of the following causes whirling of shafts

A. non-homogeneity of shaft material C. fluctuation of speed

B. misalignment of bearings D. internal damping

99. During torsional vibration of a shaft, the node is characterized by the

A. maximum angular velocity C. maximum angular acceleration

B. maximum angular displacement D. zero angular displacement

100. Which is correct statement about stress concentration in static loading is

A. very serious in brittle materials and less serious in ductile materials

B. very serious in ductile materials and less serious in brittle materials

C. equally serious in both types of materials

D. none of the above

SPUR, HELICAL GEAR, WORM GEAR, BEVEL GEAR, PLANETARY GEAR

1. A stock helical gear has a normal pressure angle of 20 deg., it has a transverse diameter pitch of
6 TPi. The teeth on the gear is 18 and the helix is 25 deg. Compute for the pitch diameter of the gear.

A. 7.62 cm B. 3 mm C. 10.3 in D. 7.6 in

2. A 15-tooth spur pinion has a module of 3 mm and runs at a speed of 1600 RPM. The driven gear
has 60 teeth. Find the speed of the driven gear.

A. 1500 RPM B. 400 RPM C. 500 RPM D. 1600 RPM

3. A gear set has a pinion with 20 teeth and a gear with 40 teeth. The pinion runs at 1800 RPM and
transmits a power of 20 kW. The length of the line of action is 19 mm, 20 deg. full depth system and
a module of 5 mm. What is the resultant force on the contacting gear tooth?

A. 2250.81 lb B. 506 lb C. 291.35 kN D. 109.3 N

4. A set of coniflex bevel gears delivers 15 hp. The outer diameter of the pinion is 10 in., face with
width is 2 in. and the rotational speed is 400 rpm. Both the gear and the pinion have 14.5 full depth
teeth. The gear runs at 150 rpm and the angle between the gear and the pinion shafts is 80 deg.,
calculate the pitch angle of the gear.

A. 60.87 deg. B. 19.13 deg. C. 87.50 deg. D. 2.5 deg.

5. An 18-tooth straight spur gear transmits a torque of 1300 N-mm. The pitch circle diameter is 2.3
cm, and the pressure angle is 37 deg. What is most nearly the tangential force on the gear?

A. 43 N B. 57 N C. 85 N D. 110 N

6. Two gears are in mesh. Gear 1 has 20 teeth and a radius of 4.6 cm. Gear 2 has 30 teeth and a
radius of 7.2 cm. What is the most nearly the diametral pitch of these two gears?

A. 110 per m B. 140 per m C. 180 per m D. 210 per m

7. An 18-tooth straight spur gear transmits a torque of 1100 N-mm. The pitch circle diameter is 19
mm, and the pressure angle is 15.5 deg. What is most nearly the radical force on the gear?

A. 16 N B. 30 N C. 110 N D. 120 N

8. Find the tooth thickness on a tooth circle of 20-deg. full depth involute tooth having a diametrical
pitch of 3, circular pitch of 1.0472 and whole depth of tooth at 0.60.

A. 10.7 cm B. 13.2 in C. 10.1 mm D. 0.52 in

9. A spur pinion rotates at 1800 rpm and transmits to a mating gear 30 HP. The pitch diameter is 5’’
and the pressure angle is 14 ½ deg. Determine the resultant load in lbs.

A. 406 B. 444 C. 525 D. 434

10. A pair of 14.15 full depth involute gears is made from cast iron of BHN value 230. The larger gear
has 50 teeth and the other one has 25 teeth. The diametrical pitch and teeth face thickness are 5 in.

A. 1066.66 lbs B. 853.26 lbs C. 2133.32 lbs D. 426. 63 lbs

11. An externally meshing gears with 32 teeth and 48 teeth have BHN of 400. If the ears are made up
of steel, what is the load stress factor?

A. 2.82 B. 2.56 C. 9.58 D. 1.90

12. A pair of mating spur gears have 14.5 deg. Full depth involute teeth 2 ½ diametral pitch. The
pitch diameter of the smaller gear is 6.4 inches. If the transmission ratio is 3 to 2. Calculate the
addendum,

A. 0.462 in B. 0.862 in C. 0.4 in D. 0.57 in

13. A set of coniflex bevel gears delivers 15 hp. The outer diameter of the pinion is 10 in., face width
is 2 in. and the rotational speed is 400 rpm. Both the gear and the pinion have 14.5 full depth teeth.
The gear runs at 150 rpm and the angle between the gear and the pinion shafts is 80 deg., calculate
the pitch angle of the pinion.

A. 60.87 deg. B. 19.13 deg C. 87.50 deg D. 2.5 deg.

14. A pinion has 15 teeth of a 3 diametrical pitch. Find the chordal thickness at the standard pitch
diameter.

A. 0.653 in B. 0.523 in C. 0.863 in D. 0.234 in

15. An epicyclic gear train with two gears A and B mesh externally are connected by an arm
between centers. Gears A and B have 40 and 50 teeth, respectively. . If the arm rotates at 200 RPM
in anticlockwise direction about the center of the gear A which is fixed, what should be the speed of
revolution of gear B in rpm?

A. 160 RPM B. 320 RPM C. 450 RPM D. 360 RPM

16. A gear is used to transmit 26.81 HP at 10 rps to a driven gear. The pinion has a pitch diameter of
200 mm. If the pressure angle is 14. 5 degrees, find the load that tends to separate the two gears.

A. 234 lb B. 0.534 kN C. 185 lbs D. 0.823 N

17. A spur gear has a module of 3 mm, number of teeth is 16 and a face width of 36 mm. It is
transmitting a power of 3 kW at 20 rev/s. Taking a velocity factor of 1.5, and a form factor of 3.0, the
stress in the gear tooth is about

A. 64 MPa B. 32 MPa C. 10 MPa D. 46 MPa

18. Two mating spur gears have 80 teeth and 240 teeth, respectively. The pinion rotates at 1200
RPM and transmits a torque of 40 N-m. Calculate the torque transmitted by the gear.

A. 0.120 N-m B. 120 N-m C. 328 in-lb D. 21.3 ft-lb

19. What is the space width of the gear if the tooth thickness is 0.205 in and the backlash is 0.005 in?
 A. 0.001 in B. 0.195 in C. 0.205 in D. 0.210 in

20. A pair of mating spur gears have 14.5 deg. Full depth involute teeth of 2 ½ diametral pitch. The
pitch diameter of the smaller gear is 6.4 inches. If the transmission ratio is 3 to 2. Calculate the
addendum.

A. 0.462 in B. 0.862 in C. 0.4 in D. 0.57 in

21. A 21-tooth spur pinion mates with a 28 tooth gear. The diametral pitch is 3 TP1 and the pressure
angle is 20 deg., compute the addendum.

A. 0.111 in B. 0.333 in C. 0.222 in D. 0.444 in

22. In a two ram hydraulic steering gear, the rams are 250 mm diameter, the rubber stock is 400 mm
diameter and the distance from center of rudder stock to center line of rams is 800 mm. Calculate
the stress in the rudder stock when the rudder is in mid-position and the hydraulic pressure is 70
bar.

A. 31.54 MPa B. 42.76 MPa C. 21.87 MPa D. 16.24 MPa

23. A double threaded right hand 3.0 in. worm gear transmit 20 hp at 1,150 rpm. The pressure angle
is 14.5 deg. And the coefficient of friction is 0.12. Find the tangential force on the gear in lbs.

A. 548 lbs B. 730.43 lbs C. 821. 74 lbs D. 620 lbs

24. A helical gear having 28 teeth and pitch diameter of 7 has a helix angle of 22 degrees. Find the
circular pitch in a plane normal to the pitch.

A. 0.528 B. 0.628 C. 0.728 D. 0.828

25. A simple epicyclic gearbox with one planet has gears with 24, 40 and 104 teeth on the sun,
planet and internal ring gears respectively. The sun rotates clockwise at 60 rpm. The ring gear is
fixed. What is the rotational velocity of the planet carrier?

A. 121.16 rpm B. 8.49 rpm C. 11.25 rpm D. 9.38 rpm

26. A 20-tooth helical gear has a pitch diameter of 5 inches . Find the normal diametral pitch if helix
angle is 22 degrees.

A. 3.31 in B. 4.31 in C. 5.31 in D. 6.31 in

27. The load on a gear tooth is 50 kN. If the gear is transmitting a torque of 6 kN-m, the diameter of
the gear is approximately

A. 0.5 m B. 0.75 m C. 1 m D. 0.25 m

28. An epicyclic gear set has an overall speed reduction of 3:1. The planet carrier is the output gear.
The input gear is the sun gear, which turns clockwise at 100 RPM. The planet has 20 teeth and a
diametral pitch of 10. What is the ratio of the number of teeth on the ring gear to the number of
teeth on the sun gear if the ring gear is part of the housing and is stationary?

A. ⅓ B. ½ C. 1 D. 2
29. A worm gear set is designed to have a pressure angle of 30 deg., which is equal to the helix angle.
The efficiency of the worm gear set an interface friction of 0.05 is

A. 78.9% B. 56.4% C. 87.9% D. 76.5 %

30. A helical gear has a diametral pitch in the normal plane of 3. The helix angle is 23 degree. If the
face width of the gear is 3-in, what is the overlap ratio?

A. 1.67 B. 1.34 C. 1.56 D. 1.12

31. Compute the pitch angle of a bevel gear given the pinion’s number of teeth of 14 and 42 teeth on
the gear.

A. 18.40 B. 33.40 C. 28.40 D. 38.40

32. In a pair of gear that connects a pair of shafts at 90𝑜 , the velocity ratio is 3 to 1. If the gear is
straight bevel, what is the cone pitch angle of smaller gear?

A. 71.57 deg B. 65.34 deg C. 18.43 deg D. 20.5 deg

33. A 20 deg. straight-tooth bevel pinion having 14 teeth and a diametral pitch of 6 teeth/inch drives
a 42-tooth gear. The two shafts are at right angles and in the same plane. Find the pitch angle of the
pinion.

A. 18.4 deg B. 20 deg C. 14.5 deg D. 20.5 deg

34. A 20 deg. full depth straight tooth gear has a face width of 3.75 in. and a pitch diameter of 12 in
with cone pitch angle of 37.5 degree. Find the mean diameter/

A. 9.72 in B. 9.02 in C. 8.48 in D. 10.72 in

35. A pair of 4-pitch, 14.5 deg., involute bevel gear has 2:1 reduction. The pitch diameter of the
driver is 10 in and face width of 3 in. Determine the face angle of the pinion.

A. 1.28 deg B. 26.565 deg C. 27.85 deg D. 25.28 deg

36. In a planetary gear train, assume that the ring gear is fixed. Also, assume that the sun gear has
32 teeth, the planet gears have 16 teeth, and the ring or internal gear has 64 teeth. The sun gear
rotates 100 rpm clockwise. Find the rotational speed of the planet carrier.

A. 28 rpm B. 200 rpm C. 50.0 rpm D. 33.3 rpm

37. A helical gear has a normal diametral pitch of 8, a normal pressure angle of 20 deg., and helix
angle of 15 deg., 32 teeth and face width of 3 in. The gear rotates at 650 RPM while transmitting 7.5
HP. What is the tangential force on the gear?

A. 351 lb B. 132 lb C. 94 lb D. 182 lb

38. A double thread worm has a normal pressure angle of 14.5, a pitch diameter of 3.5 in and lead
of 1.5 in. Find the pressure angle of the worm.

A. 11.68𝑜 B. 12.68𝑜 C. 13.68𝑜 D. 𝟏𝟒. 𝟔𝟖𝒐

39. A fixed gear having 200 teeth is in mesh with another gear having 50 teeth. The two gears are
connected by an arm. The number of turns made by the smaller gear for one revolution of arm
about the center of the bigger is

A. 2/4 B. 3 C. 4 D. 5

40. A double thread worm has a lead angle of 7.25o and pitch radius of 2.5. Determine the pitch of
the worm.

A. 1.5 inch B. 2 inches C. 1.5 inch D. 0.75 inch

41. A helical gear has a normal diametral pitch of 8, a normal pressure angle of 20 deg., and helix
angle of 15 deg., 32 teeth and face width of 3 in. The gear rotates at 650 RPM while transmitting 7.5
HP. What is the axial force on the gear?

A. 351 lb B. 132 lb C. 94 lb D. 182 lb

42. A double-thread worm has a pitch diameter of 3 inches. The wheel has 20 teeth and a pitch
diameter of 5 inches. Find the gear helix angle.

A. 4.69𝑜 B. 𝟗. 𝟒𝟔𝒐 C. 6.49𝑜 D. 6.94𝑜

43. A triple-thread worm has lead angle of 17𝑜 and pitch diameter of 2.2802 inches. Find the center
distance when the worm is mated with wheel of 48 teeth.

A. 6.72 inches B. 7.26 inches C. 6.27 inches D. 7.62 inches

44. A work rotating at 1150 rpm drives a worm gear. The velocity ratio is 15 to 1. A 10 hp motor is
used to supply the worm with worm pitch gear diameter of 3 in. Find the tangential force on the
worm.

A. 548.05 lb B. 182.68 lb C. 274.025 lb D. 365.37 lb

45. A worm gear reducer unit is to have a 16-inch center distance. What should be the approximate
worm diameter.

A. 2.14 in B. 3.15 in C. 5.14 in D. 4.15 in

46. A worm gear reducer unit is to have 16-in center distance What should be the axial pitch.

A. 1.71 B. 1.16 C. 1.21 D. 1.98

47. Find the number of teeth in the worm-wheel of worm driven screw jack to give a velocity ratio of
570 if the worm is single threaded, the screw has pitch of 16 mm and the effort wheel is 100 mm
diameter?

A. 29 B. 30 C. 28 D. 24

48. A double thread worm gear has pitch of 1.125 inches and a pitch diameter of 3 inches. It has a
coefficient of friction of 0.20 and normal pressure angle of 14.5o. The worm is supplied by 12 Hp at
1200 rpm motor. Find the tangential force on the gear. The worm is a left-hand thread.

A. 420 lb B. 897 lb C. 789 lb D. 879 lb

49. If the annular wheel of an epicyclic gear train has 100 teeth and the planet wheel has 20 teeth,
the number of teeth on the sun gear is?

A. 80 B. 60 C. 40 D. 20

50. Two meshing spur gears with ratio 3:2 have center distance equal to 15 inches. The gears are
14.5 deg full depth involute with diametral pitch of 4. Determine the contract ratio.

A. 1.23 B. 2.18 C. 1.34 D. 2.81

51. How are gears for watches generally manufactured?

A. Die casting B. Machining on hobber C. Power metallurgy process D. Stamping

52. Which of the following where the gear tooth Vernier is used to measure?

A. Module B. Gear tooth profile

C. Gear tooth thickness of gear tooth D. Pitch line thickness of gear tooth

53. When the velocity ratio is high and space is limited, use

A. Spur gear B. Bevel gear C. worm gear D. helical gear

54. Which of the following type of gears are used for noiseless operation?

A. Spur gears B. bevel gears C. worm gears D. helical gears

55. Compared with spur gears, helical gears

A. Run more smoothly B. run with noise and vibrations

C. Consume less power D. run exactly alike

56. The main function of an automobile gearbox is

A. To reduce speed B. To increase speed

C. To provide variable speeds D. to increase power

57. For transmitting power, a simple gear train consisting of 11 gears is used. Then the driver and
driven shafts will be rotating in

A. Same direction B. opposite direction

C. same or opposite direction D. none of the above

58. A thickness of gear tooth is measured

A. Along the pitch circle C. along the addendum

B. Along the base circle D. Along the root circle

59. The whole depth of for a pair of gears is given by

A. Addendum plus dedendum C. twice the addendum

 B. Twice the addendum D. dedendum minus addendum

60. The curves the satisfy fundamental law of gearing are,

A. Cycloid B. spiral C. involute D. A and C

61. Which of the following types of gear is free from interference?

A. Cycloidal gear B. spiral gears C. involute gears D. stub gears

62. Spur gears used for machine tool gearboxes must have the contact ratio

A. Equal to 1 B. less than 1 C. more than 1.4 D. equal to 2

63. Reducing pressure angle on gears results in

A. Weaker teeth C. high velocity ratio

B. Stronger teeth D. high efficiency

64. In lewis equation, fear tooth is considered as

A. Simply supported beam C. curved beam

B. Cantilever beam D. none of the above

65. Permissible bending stress for gear tooth is usually taken as

A. One third of ultimate strength

B. One half of ultimate tensile strength

C. One third of tensile yield strength

D. One third of surface endurance strength

66. Static force on gear tooth is due to

A. Power transmitted by gears C. acceleration of gears

B. Misalignment in bearings D. bearing reactions

67. Non-metallic gears have

A. Low noise and low load carrying capacity

B. Low noise and high load carrying capacity

C. High noise and high load carrying capacity

D. High noise and low load carrying capacity

68. When two bevel gears having equal teeth and equal pitch angle are used to transmit power
between shafts and are intersecting at right angle, they are called

A. Spiral bevel gears C. straight bevel gears

 B. Miter gears D. hypoid gears

69. Incase of zerol gears, the axes of shafts are

A. Intersecting and teeth are straight

B. Intersecting and teeth are curved

C. Non-parallel and non-intersecting and teeth are straight

D. Non-parallel and non-intersecting and teeth are curved

70. In a concrete mixer, the bevel gears for rotating the drum are generally made by

A. Casting B. forging C. hobbing D. shaping

71. Which type of gears are used for shaft axes having an offset

A. Hypoid gear B. spiral bevel gear C. zerol gear D. mitre gear

72. The angle at the base cylinder of an involute gear, that the tooth makes with the gear axis

A. Base helix angle C. arc of recess

B. Pressure angle D. arc of approach

73. An imaginary circle passing through the points at which the teeth of the meshing gears contact
each other

A. Pitch circle C. dedendum circle

B. Addendum circle D. base circle

74. When meshed with a gear, it is used to change rotary motion to reciprocating motion.

A. Gear shaft B. gear tooth C. gear rack D. gear motor

75. The clearance between the tooth profiles of a gear tooth

A. Tooth space B. backlash C. flank D. width

76. In the gear design, the total workload must be equally shared by its arms. Rim must be rigid to
support these arms and also the head is recommended for its stiffening value. The assumption in
the detailed design of rim thickness and depth of bead is _______ circular pitch (PC).

A. 0.65 B. 0.50 C. 0.56 D. 0.44

77. Gear used to transmit power at high velocity ratios between non-intersecting shafts that are
usually but not necessarily at right angle

A. Helical gear B. bevel gear C. worm gear D. spiral gear

78. For evenly distributed and uniform wear on each meshing gear tooth, the ideal design practice
is to consider a:
 A. Wear resistance alloy addition to tooth gear

B. Heat treatment of the gears

C. Hardening of each tooth

D. Hunting tooth addition

79. What will be the effect in bushing gears without backlash?

A. Jamming B. overheating C. overload D. all of these

80. The train value of the gear train is______.

A. Equal to the speed ratio C. half of the speed ratio

B. Double the speed ratio D. reciprocal of the speed ratio

81. A reverted gear train is one in which the output shaft and input shaft

A. Rotate in opposite directions C. are at right angles to each other

B. Are coaxial D. are at angle to each other

82. When two shafts are neither parallel nor intersecting, power can be transmitted by using

A. A pair of spur gears C. an oldham’s coupling

B. A pair of helical gears D. a pair of spiral gears

83. In a simple gear train, if the number of idle gears is odd, then the direction of motion of driven
gear will

A. Be same as that of driving gear

B. Be opposite to the driving gear

C. Depend upon the number of teeth on the driving gear

D. Depend upon the total number of teeth on all gears of the train

84. Which type of gear will be used to have minimum axial thirst

A. Helical gears C. hypoid gears

B. Herringbone gears D. worm gears

85. Spiral gears are suitable for transmitting

A. Small power B. Huge power C. no power but motion D. any power

86. Spring driven watches and clocks utilize

A. Involute gears C. epicycloid gears

B. Cycloid gears D. straight rack gears

87. Backlash in spur gears is the

A. Difference between the dedendum of one gear and the addendum of the mating gear

B. Difference between the tooth space of one gear and tooth thickness of the mating gear
measured on the pitch circle

C. Intentional extension of center distance between two gears

D. Does not exist

88. Surface endurance limit of gear material is dependent on its

A. coefficient of elasticity C. brinell hardness number

B. Elastic strength D. yield strength

89. Tubular gears are the gears used in

A. Milling machine to change direction of rotation by 90 deg

B. Lathe for reversing direction of rotation

C. Lathe for increasing /decreasing cutting speed

D. Lathe for cutting threads

90. Automobile steering gear is an example of

A. Higher pair B. Lower pair C. turning pair D. rotary pair

91. Davis steering gear consist of

A. Sliding pairs C. rolling pairs

B. Turning pairs D. higher pairs

92. Ackerman steering gears consists of

A. Sliding pairs C. rolling pairs

B. Turning pairs D. higher pairs

93. To obviate axial thrust, following gear drive is used

A. Double helical gears having opposite teeth

B. Double helical gears-living identical teeth

C. Single helical gear in which one of the teeth of helix angle is more

D. Miter gears

94. Pitch circle diameter of an involute gears is

A. Independent of any other element C. constant for a set of meshing gears

 B. Dependent of pressure angle D. proportional to base diameter

95. In an involute gear, the normal to the involute is tangent to the

A. Pitch circle C. addendum circle

B. Base circle D. dedendum circle

96. Gears are considered to be medium velocity type if their peripheral velocity lies the range of

A. 1-3 m/sec B. 3-15m/sec C. 15-25m/sec D. 25-50m/sec

97. The gear train in which the first and last gear are on the same axis, is known as

A. Uniaxial gear train C. compound gear train

B. Reverted gear train D. epicyclic gear train

98. The path of contact in involute gears is

A. A straight line B. involute gears C. curved line D. circle

99. Which is false statement about involute gears

A. Pressure angle varies from zero at pitch to maximum at commencement and end of
engagement

B. Slight variation in center distance can be tolerated

C. Simple tools required for manufacture

D. Smooth running

100. The gear box in automobiles is placed between

A. The clutch and differential C. the engine and clutch

B. The steering and engine D. the differential and Hook’s joint

BEARINGS, FLYWHEELS, SPRINGS, BELTS, CHAIN DRIVE, WIRE ROPE

1. A closely coiled spring of 20 cm mean diameter is having 25 coils of 2 cm diameter. Modulus of

rigidity of the material is 10 x 10 (raised to 7) N/cm2. Stiffness of spring is
 A. 50 N/cm B. 250 N/cm C. 500 N/cm D. 100 N/cm

2. A body weighing 4.45 kN falls from a height of 15.24 cm and strikes a 350 kN/m spring. The
deformation of the spring is?

A. 0.076 in B. 25.76 cm C. 76.25 mm D. 32.47 in

3. A bumper consisting of two helical springs of circular section brings to rest a railway wagon of
mass 1500 kg and moving at 1 m/s. While doing so, the springs are compressed by 150 mm. Then,
the maximum force on each spring (assuming gradually increasing load) is.

A. 2.5 kN B. 5 kN C. 7.5 kN D. 3 kN

4. A cast-steel flywheel has a specific weight of 0.28 𝑙𝑏/𝑖𝑛3 . The allowable hoop stress is to be 500
psi. Find the maximum velocity of the rim at the mean radius.

A. 90.9 fps B. 72.6 fps C. 80.7 fps D. 70.8 fps

5. A coil-spring of stiffness 4 kN.m is cut exactly at the middle and the two springs thus made are
arranged in parallel to take up together a compressive load. The equivalent stiffness of the two
springs is.

A. 4 kN/m B. 8kN/m C. 16kN/m D. 24kN/m

6. A heavy-duty sleeve bearing is used with good ventilation. The bearing has a diameter of 2 in. and
a length of 6 in. The load on the bearing is 1.1 kips. A shaft rotates 200 rom in the bearing and does
not transmit any heat to the bearing other than that due to shaft-bearing friction. The coefficient of
friction is 0.02 and the ambient temperature is 75 deg F. Find the probable operating temperature of
the bearing.

A. 131.75 deg F B. 119.15 deg C C. 48.41 deg C D. 131.50 deg F

7. Find the centrifugal force of a cast iron flywheel with a mean rim radius of 228.6 mm, when
rotated at a speed of 13.33 rps. If the weight of the rim is 89 N.

A. 14.454 lb B. 15545 N C. 3269.34 lb D. 14.54kN

8. What is the bursting speed for a cast iron having a tensile strength of 20,000 psi?

A. 456.22 ft/s B. 444.21 ft/s C. 546 ft/s D. 436 ft/s

9. A punch press is to have a capacity of 3.628 kN through a 25.4-mm stroke. For the efficiency and
cost of a small motor, a flywheel was used. What flywheel effect is required to maintain the
flywheel within 20% of its no-load speed of 600 rpm? In-lb-s2

A. 2.8 𝑘𝑔 − 𝑚 − 𝑠2 B. 3.4 𝑖𝑛 − 𝑙𝑏 − 𝑠2

C. 0.045 𝑖𝑛 − 𝑙𝑏 − 𝑠2 D. 𝟎. 𝟎𝟑𝟐𝟐 𝒌𝒈 − 𝒎 − 𝒔𝟐

10. Determine the maximum allowable tensile stress in a cast iron flywheel effect if the permissible
velocity is 205 fps. The cast iron weighs 0.255 lb/cu. In.

A. 3994 kPa B. 1.25 ksi C. 27.53 MPa D. 3994 ksi

11. An engine is designed to develop 13.40 HP of power at a mean speed of 16.67 rps. Compute the
coefficient of fluctuation of speed of a suitable flywheel if the speed variation is ± 1.5% of the
mean speed.

A. 0.015 B. 0.00 C. 0.03 D. 0.014

12. A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/10 inch.
Determine the value of Bergstrassar factor of the spring.

A. 1.172 B. 1.712 C.1.217 D. 1.135

13. What is the natural frequency of an oscillating body whose period of oscillation is 2pi s?

A. 3.5 rad/s B. 2.00 rad/s C. 3.14 rad/s D. 1.00 rad/s

14. A 25 in. long cantilever spring is composed of 8 graduated leaves and one extra full-length leaf.
The leaves are 1.5 in wide. A load of 600 lb at the end of the spring causes a deflection of 2 inches.
Determine the maximum bending stress in the full-length assuming that the first extra full-length
leaf has been pre-stressed to give the same stress in all leaves.

A. 80,100 psi B. 50,000 psi C. 60,000 psi D. 40,900 psi

15. A mass, m, of 0.030 kg is hanging from a spring whose spring constant, k, is 0.55 N/m. If the
mass is pulled down and released, what is the period of oscillation?

A. 1.34 s B. 0.50 s C. 1.5 s D. 1.467 s

16. How long a wire is needed to make helical spring having a mean diameter of 1 inch if there are 8
active coils?

A. 25.13 in B. 26.65 in C. 30.21 in D. 32.34 in

17. Springs A and B have spring constants of 2kN/m and 1 kN/m respectively. Spring A is yung from
a rigid horizontal beam and its other end is attached to an end of spring B. The pair of springs is then
used to suspend a body mass of 50 kg from the lower end of spring B. What is the period of
harmonic oscillation of the system?

A. 1.09 B. 1.72 C. 1.45 D. 2.01

18. A semi-elliptical spring is to sustain a load of 800 lb. It consists of one full-length leaf and seven
graduated leaves. The leaf width is 2 in. The total length of the spring is 42 inches and U-bolts at the
center deactivate 2 inches of length. The allowable stress is 50,000 psi and the modulus of
elasticity is 30,000,000 psi. Find the thickness of the leaves.

A. 0.172 in B. 0.324 in C. 0.245 in D. 0.220 in

19. A 25 in. long cantilever spring is composed of 8 graduated leaves and one extra fell-length leaf.
The leaves are 1 3 4 in wide. A load of 350 lb at the end of the spring causes a deflection of 2 inches.
Determine the thickness of the leaves.

A. 0.4362 in B. 0.6532 in C. 0.2356 in D. 0.3204 in

20. Neglecting spoke effect, calculate the energy stored in the rim of a flywheel made of cast iron
24 in. in diameter, having a rim 5 inches wide by 4 inches deep when running at 1000 rpm. The
internal radius of the rim is 8 inches. Note: density of a material is 450 lb/cu.ft.

A. 40, 122.28 ft-lb B. 38,614.21 ft-lb C. 58,234.36 ft-lb D. 50,165.32 ft-lb

21. A long helical spring having a spring stiffness of 12 kN/m and with a number of turns of 20,
breaks into two parts. What is the stiffness of the resultant spring?

A. 6kN/m B. 24kN/m C. 12 kN/m D. 30 kN/m

22. Two identical ball bearings A and B are operating at loads 30 kN and 45 kN respectively. The
ratio of the life of bearing A to the life of bearing B is.

A. 81/16 B. 27/8 C. 9/4 D. 3/2

23. If a 650 mm diameter, steel flywheel of constant thickness is used, how thick should it be? The
specific gravity of steel is 7.85. The inertia of flywheel is 18.31 kg-m (squared)

A. 3.54 in B. 5.24 in C. 13.33 in D. 1.45 in

24. A journal bearing has a shaft diameter of 40 mm and a length of 40 mm. The shaft is rotating at
20 rad/s and the viscosity of the lubricant is 20 mPa-s. The clearance is 0.020 mm. The loss of
torque due to the viscosity of the lubricant is approximately.

A. 0.040 N-m B. 0.252 N-m C. 0.400 N-m D. 0.652 N-m

25. A 35 in. long cantilever spring is composed of 8 graduated leaves and one extra full-length leaf.
The leaves are 1 3 4 in. wide. A load of 500 lb at the end of the spring causes a deflection of 3 in.
Determine the stress in the full extra length leaf assuming no pre-stress.

A. 49,500 psi B. 50,500 psi C. 48,500 psi D. 47,500 psi

26. A bullet of mass 100 g is fired at a wooden block resting on a horizontal surface. A spring with
stiffness k =53 kN/cm resists the motion of the block. If the maximum displacement of the block
produced by the impact of the bullet is 3.4 cm, what is most nearly the velocity of the bullet impact?
Assume there are no losses at impact, and the spring has no mass.

A. 250 kph B. 450 kph C. 630 kph D. 890 kph

27. A cantilever beam with an end mass of 7000 kg, deflects 5 cm when a force of 5 kN is applied at
the end. The beam is subsequently mounted on a spring of stiffness 1.5 kN/cm. What is most nearly
the natural frequency of the mass-beam-spring system?

A. 1.5 rad/s B. 3.1 rad/s C. 6.0 rad/s D. 6.3 rad/s

28. A ball bearing operating at a load F gas 8000 hours of life. Compute the life of the bearing, in
hours, when the load is doubled.

A. 8000 B. 6000 C. 4000 D. 1000

29. The effective radius of the pads in a single-collar thrust block is 150 mm and the total load on
the thrust block is 150 kN when the shaft is running is 150 RPM. Taking the coefficient of friction
between thrust collar and pads as 0.02. Determine the power loss due to friction.

A. 9.02 kW B. 7.07 kW C. 5.52 kW D. 15.2 kW

30. An oil ring bearing of transmission shaft of 50 mm diameter on which the journal rotates at 1450
RPM, radical clearance and bearing pressure are 20 micron and 4 MPa. If Sommerfeld number is
0.0637, the viscosity of lubricant is

A. 5.75 cp B. 6.75 cp C. 15.75 cp D. 16.75 cp

31. The rim of a spoked cast-iron flywheel in a punch press has a radius of gyration of 38.1 cm and a
face width of 30.5 cm. The flywheel rotates at 200 rpm. It supplies 2 kJ of energy and slows to 175
rpm each time a punch press is cycled. The density of the cast iron is 7200 kg/ms. The hub and
arms increase the rotational moment of inertia by 10%. What is the rim thickness?

A. 7.4 mm B. 4.7 in C. 1.9 in D. 3.5 in

32. The flywheel of a machine having weight of 4.5 kN and radius of gyration of 2 m has cyclic
fluctuation of speed from 125 RPM to 120 RPM. Compute the maximum fluctuation of energy.

A. 12.1 kN-m B. 12.324 kJ C. 32.341 kN-m D. 12039 J

33. In a flywheel, the safe stress is 25.2 MPa and the specific gravity is 7. Compute the maximum
peripheral velocity.

A. 120 m/s B. 60 ft/s C. 197 ft/s D. 30 m/s

34. A riveting machine is driven by a constant-torque 3 kW motor. The moving parts including the
flywheel and equivalent to 150 kg at 0.6 m radius. One riveting operation take 1 second and absorbs
10 kN-m of energy. The speed of the flywheel is 300 RPM before riveting . What is the speed after
riveting?

A. 829 RPM B. 290 RPM C. 390 RPM D. 260 RPM

35. A particular roller bearing has a life of 3000 hours when carrying an equivalent radial load of 9.5
kN and rotating at 500 rpm. What is most nearly the predicted life if the bearing is loaded to 12 kN at
the same rotational speed?

A. 1000 hours B. 1200 hours C. 1300 hours D. 1400 hours

36. Find the stress on a single-leaf cantilever spring, assuming the thickness and width of the leaf
are 1/8 -in and 1/4-in, respectively. A load of 5 is applied at a distance of 10 inches from a support.

A. 101,920 psi B. 89,332 psi C. 76,800 psi D. 18,912 psi

37. Find the deflection on a single-leaf cantilever spring, assuming the thickness and width of the
leaf are 1/8-in and 1/4 -in, respectively. A load of 5 lb is applied at a distance of 10 inches from a
support. Use 𝐸 = 30 × 106 𝑝𝑠𝑖.

A. 1.22 in B. 1.36 in C. 1.91 in D. 1.02 in

38. A semi-elliptical single-leaf cantilever spring has a load of 80 lb acting at its center. Distance L =
6 in., the leaf thickness is ⅛ in., and the width of the leaf ½ in. The modulus of elasticity is 30,000,00
psi. Find the deflection for this load.

A. 0.148 in B. 0.221 in C. 0.741 in D. 0.412 in

39. Find the belt length at a 72 in distance for a crossed belt connection with pulley diameter of 6
and 12 in, respectively.

A. 162.34 in B. 173.39 in C. 123.55 in D. 172.39 in

40. A no.40, roller chain operates at 1100 rpm between 16 tooth and 30 tooth sprockets. If the
center distance between the sprockets is 20 in., running condition being normal, calculate the
average chain velocity. Note: the pitch of No.40 roller chain is ½ in.

A. 675.45 fpm B. 1254.54 fpm C. 548.75 fpm D. 748.75 fpm

41. A machine competent is driven by a 6 kW motor using a standard classical A70 V- belt. The
nominal speed of the motor be 500 RPM. The motor’s sheave diameter is 10 in. What is the pitch
length of the belt?

A. 70 in B. 181 cm C. 92 mm D. 2332 mm

42. Calculate the allowable tension of a roller chain of ⅝ in pitch used on a sprocket with 34 teeth
which rotates at 500 rpm.

A. 176.6 lbs B. 186.66 lbs C. 196.66 lbs D. 200.39 lbs

43. A piece of equipment is driven by a 15 HP motor through a standard B80 V-belt. The motor runs
at 1850 RPM. The nominal speed of the equipment must be 900 RPM. The motor’s sheave diameter
is 10 in. What is the pitch length of the belt?

A. 81.8 cm B. 80 in C. 208 cm D. 2322 mm

44. A 5V 3350 drive belt is connected to a normal torque squirrel-cage electric motor operating at
1850 RPM. Sheaves for both driver pulley are 318 mm in diameter. Find the center distance given
that the length of this type of belt is 815 cm.

A. 86.5 cm B. 147.865 mm C. 33.234 cm D. 7.75 m

45. A block and tackle have an ideal mechanical advantage of 4. If this device uses Manila rope with
a breaking strength of 3000 lb, what safe load can be handled if a factor of safety of 6 is to be used?

A. 13,250 lb B. 18,000 lb C. 663 lb D. 500 lb

46. Find the bending stress and equivalent bending load due to the bending of a 6 x 19 (fiber core)
wire rope of ½ in diameter around a 24 in pitch diameter sheave.

A. 1456 lbs B. 1590 lbs C. 1983 lbs D. 1763 lbs

47. A 4-ton weight is raised at a constant acceleration of 3 fps2. What is the cable stress in raising
the load?
 A. 6745.34 kg B. 3751.55 kg C. 3059.11 kg D. 3966.14 kg

48. A 6 x 19 IPS wire rope diameter of 54.5 mm is to be used for hoisting. Find the weight of the rope
if the depth of mine hoist is 150 m

A. 1161.31 lb B. 1218.23 lb C. 2491.83 lb D. 3625.29 lbs

49. A wire rope is used with total load of 9,000 kg and bending load of 50,000 kg. If bearing strength
of the rope is 110,000 kg, find the factor of safety of the rope.

A. 7.76 B. 6.67 C. 9.67 D. 8.67

50. A steam turbine rated at 20 HP and 1200 rpm runs a centrifugal compressor at a velocity ratio of
3. If no. 50 chains is to transmit power, if the service factor for engine drive and moderate shock
conditions is 1.3, and the recommended number of teeth on the smaller sprocket is 21, estimate
the pitch of the smaller sprocket.

A. ⅝ cm B. 0.75 in C. 15.88 mm D. 16.44 in

51. Which of the following statements is correct for an oilness bearing?

A. The oil film is maintained by supplying oil under pressure

B. The oil film pressure is produced only by rotation of the journal

C. Do not need external supply of lubricant

D. Grease is needed to be applied after some intervals

52. It is the ability to deform plastically to compensate for irregularities in bearing assembly. How
do you call this?

A. Plasticity B. Conformability C. Embeddability D. Elasticity

53. To avoid scoring in the bearing surface and the shaft due to contamination or absorption of the
fine dirt in the bearing during operation/lubrication the bearing material to apply should have good
_________ properties,

A. Anti-scoring C. Corrosion resistance

B. Embeddability D. Corrosion resistance conformability

54. The cast iron flywheels are commonly designed with a factor of safety of _______

A. 14 to 15 B. 8 to 9 C. 10 to 13 D. 6 to 12

55. Which of the following wires with good quality and is used for impact loading?

A. Hard drawn wire C. Helical spring wire

B. Cold drawn wire D. Chromium-silicon wire

56. Cut pieces from flat plates, strips and coil stock.

A. Shearing B. Bend allowance C. Forming dies D. Spring back

57. It is a lubrication for roller chains wherein the lubricant is supplied by a circulating pump
capable of supplying the chain drive with a continuous flow of oil inside the chain loop evenly
across the chain width and directly at the slack.

A. Oil stream lubrication C. Drip lubrication

B. Bath lubrication D. Recirculated lubrication

58. The working load P for a chain for crane applications is expressed in terms of diameter of link “d”
in cm follows.

A. 𝑃 = 1.52𝑑 2 B.𝑃 = 25𝑑 2 C. 𝑃 = 50𝑑 2 D. 𝑷 = 𝟓𝟎𝟎𝒅𝟐

59. Spring back metal forming depends on ___________

A. Strain rate B. Modulus of elasticity C. load applied D. none of these

60. What is the best method for increasing a spring’s fatigue life?

A. Bombarding B. stress relieving C. short peening D. short relieving

61. The maximum shear stress occurs on the outermost fiber of a circular shaft under torsion. In a
close-coiled helical spring the maximum shear stress occurs on the

A. Outermost fiber C. inner most fiber

B. Fiber at mean diameter D. end coils

62. The compliance of the spring is the:

A. Reciprocal of the spring constant

B. Deflection of the spring under compressive load

C. Force required to produce a unit elongation of the spring

D. Square of the stiffness of the spring

63. There are two basic types of torsion springs, one of which is the flat coil springs also known as
power spring or

A. Clock spring C. leaf spring

B. Helical spring D. time spring

64. For the rotating elements like flywheels and blowers, the analysis of stresses will be based on
the following theory?

A. Thin-walled cylinder C. radial ball bearing

B. Thick-walled cylinder D. rotating shaft member

65. What is the recommended coefficient of fluctuation of flywheels for punching, shearing,
pressing machines?
 A. 0.005-0.1 B. 0.007-0.01 C. 0.03-0.05 D. 0.01-0.03

66. The cast iron flywheels are commonly designed with a factor of safety of _______.

A. 14 to 15 B. 8 to 9 C. 10 to 13 D. 6 to 12

67. A general rule of thumb of cast-iron rim flywheels of average size is that the mean velocity
should not exceed:

A. 3000 fpm B. 4000 fpm C. 5000 fpm D. 6000 fpm

68. In radial bearings, the load acts

A. Along the axis of rotation

B. perpendicular to the axis of rotation

C. Parallel to the axis of rotation

D. A and C

69. Rolling contact bearings as compared to sliding contact bearings have

A. Lower starting torque C. generate less noise

B. Require considerable axial space D. costly

70. A bearing is designated by the number 410. It means that it is a bearing of

A. Light series with bore diameter of 10 mm

B. Heavy series with bore diameter of 50 mm

C. Medium series with bore diameter of 50 mm

D. Light series with bore diameter of 50 mm

71. In an application, the bearing is subjected to radial as well as axial loads. Which type of rolling
contact bearings would you suggest?

A. Cylindrical roller bearing C. thrust ball bearing

B. Needle roller bearing D. taper roller bearing

72. In case of full journal bearing, the angle of contact of the busing with journal is

A. 60 deg B. 90 deg C. 180 deg D. 360 deg

73. A thin film bearing is a bearing

A. Where the surfaces of journal and the bearing are completely separated by a film of
lubricant

B. Where the surfaces of journal and the bearing are partially separated by a film of
lubricant and there is partial metal to metal contact
 C. Where the surfaces of journal and the bearing are separated by a film created by elastic
deflection of parts

D. Where there is no lubricant

74. For hydrodynamic lubrication

A. There should be relative motion between the surfaces of the journal and the bearings
and wedge shaped clearance space

B. There should be external source like pump to supply lubricant under pressure

C. There should be elastic deformation of the parts in contact

D. There should be metal to metal contact

75. In most of internal combustion engines, crankshaft bearings is

A. Hydrodynamic journal bearing C. ball bearings

B. Hydrostatic journal bearing D. roller bearings

76. The property of the bearing material to yield and adopt its shape to that of journal is called

A. Embeddability C. viscosity

B. Conformability D. endurance limit stress

77. It is a type of spring where thin flat strip wound up on itself as a plane spiral, usually anchored at
the inside end

A. Motor spring C. volute spring

B. Garter spring D. helical spring

78. Which of the following alloying is used in springs to make it more reliant?

A. Silicon B. Tungsten C. hardness D. nickel

79. The property of the bearing material to allow the dust and abrasive particle to get absorbed on
the surface of the lining is called

A. Embeddability C. viscosity

B. Conformability D. endurance limit stress

80. The maximum fluctuation of energy of flywheel is

A. Difference between maximum and minimum kinetic energy during the cycle

B. difference between maximum and mean kinetic energy during the cycle

C. difference between mean and minimum kinetic energy during the cycle

D. Mean of maximum and minimum kinetic energy during the cycle

81. The rim of the flywheel is subjected to

A. Direct tensile stress and bending stress

B. Torsional shear stress and bending stress

C. Direct shear stress and bending stress

D. Compressive stress and bending stress

82. The cross section of the flywheel arm is

A. I section B. rectangular C. elliptical D. circular

83. For finding out the bending moment for the arm (spoke) of flywheel, the arm is assumed as

A. A cantilever beam fixed at the rim and subjected to tangential force at the hub

B. A simply supported beam fixed at the rim and carrying uniformly distributed load

C. A cantilever beam fixed at the hub and subjected to tangential force at the rim

D. A fixed beam fixed at hub and rim and carrying uniformly distributed load

84. Which of the following type of spring used to absorb and release energy in mechanical watches?

A. Helical compression spring C. spiral spring

B. Multi-leaf spring D. helical torsion spring

85. Which of the following type of spring used in vehicle clutches?

A. Helical compression spring C. A and B

B. Belleville spring D. helical torsion spring

86. When the helical compression spring is subjected to axial compressive force, the type of stress
induced in the spring wire is

A. Tensile stress C. bending stress

B. Compressive stress D. torsional shear stress

87. When a helical spring is cut into two halves, the stiffness of each half spring will be

A. Same as original spring C. half of original spring

B. Double of original spring D. torsional shear stress

88. Concentric springs are used

A. To achieve greater load carrying capacity with given space

B. To achieve fail-safe system

C. To eliminate surge
 D. All of these

89. Wire rope are used in applications with

A. Low speed and low tension C. high speed and high tension

B. Low speed and high tension D. high speed and low tension

90. When the wire rope passes around the sheave or drum, the stress is maximum

A. In outer wires C. in central wire

B. In inner wires D. none of the above

91. The wires in wire rope are subjected to

A. Tensile stress C. shear stress

B. Tensile and bending stress D. crushing stress

92. Based on experience, what is the most economical design belt speed?

A. 6000 to 7500 fpm C. 3000 to 5000 fpm

B. 3500 to 4700 fpm D. 5000 t0 1000 fpm

93. The tension in the belt due to centrifugal force increasing rapidly above about

A. 1500 fpm B. 3500 fpm C. 3000 fpm D. 2500 fpm

94. What is the recommended speed for fabric belts?

A. 4000 to 5000 fpm C. 3000 to 4000 fpm

B. 2000 to 3000 fpm D. 2000 and more fpm

95. Effective stress in wire ropes during-normal working is equal to the stress due to

A. Axial load plus stress due to bending

B. acceleration/retardation of masses plus stress due to bending

C. Axial load plus stress due to acceleration/retardation

D. Bending plus stress due to acceleration/retardation

96. In an oil-lubricated journal bearing, coefficient of friction between the journal and the bearing

A. Remains constant at all speeds

B. Is minimum at zero speed and increases monotonically with increases in speed

C. Is maximum at zero speed and decreases monotonically with increase in speed

D. Becomes minimum at an optimum speed and then increases with further increase in
speed
97. Removal of metal particles from the raceway of a rolling contact bearing is a kind of failure of
bearing known as

A. Pitting B. wearing C. spalling D. scuffing

98. The bearing characteristics number in a hydrodynamic bearing depends upon

A. Length, width and load C. viscosity, speed and load

B. Length, width and speed D. viscosity, speed and bearing pressure

99. While calculating the stress induced in a closed coil helical spring, wahl factor must be
considered to account for

A. The curvature and stress augmentation effect

B. Shock loading

C. Poor service conditions

D. Fatigue loading

100. Under axial load, each section of a close-coiled helical spring is subjected to

A. Tensile stress and shear stress due to load

B. Compressive stress and shear stress due to torque

C. Tensile stress and shear stress due to torque

D. Torsional and direct shear stress