# Machine Design MCQ Objective Question and Answers Part 4

Machine Design Multiple choice Objective Question useful for technical Aptitude test.

Machine Design MCQ : Part 1 | Part 2 | Part 3 | Part 4

101. The piston rod of a steam engine is usually connected to the crosshead by means of
(a) bolted joint
(b) kunckle joint
(c) cotter joint
(d) universal joint
(e) universal coupling.
Ans: c

102. Which of the following pipe joints would be suitable for pipes carrying steam
(a) flanged
(c) bell and spigot
(d) expansion
(e) compression.
Ans: d

103. Spring index is
(a) ratio of coil diameter to wire diameter
(b) load required to produce unit deflection
(c) its capability of storing energy
(d) indication of quality of spring
(e) nothing.
Ans: a

104. The shearing stresses in the inner face as compared to outer face of the wire in a heavy close coiled spring is
(a) larger
(b) smaller
(c) equal
(d) larger/smaller depending on diameter of spring coil
(e) unpredictable.
Ans: a

105. Form coefficient of spring is
(a) ratio of coil diameter to wire diameter
(b) load required to produce unit deflection
(c) its capability of storing energy
(d) concerned With strength of wire of spring
(e)  nothing
Ans: c

106. Spring stiffness is
(a) ratio of coil diameter to wire diameter
(b) load required to produce unit deflection
(c) its capability of storing energy
(d) its ability to absorb shocks
(e) none of the above.
Ans: b

107. When two springs are in series (having stiffness K), the equivalent stiffness will be
(a) K
(b) K/2
(c) 2K
(d) KIA
(e) UK.
Ans: b

108. When a close coiled helical spring is compressed, its wire is subjected to
(a) tension
(b) shear
(c) compression
(d) all of the above
(e) none of the above.
Ans: a

109. If a spring is cut down into two springs, the stiffness of cut springs will be
(a) half
(b) same
(c) double
(d) unpredictable
(e) none of the above.
Ans: c

110. Belt slip may occur due to
(b) loose belt
(c) driving pulley too small
(d) all of the above
(e) none of the above.
Ans: d

111. Aircraft body is usually fabricated by
(a) welding
(b) precasting
(c) rivetting
(d) casting
(e) unconventional methods.
Ans: c

112. If two springs are in parallel then their overall stiffness will be
(a) half
(b) same
(c) double
(d) unpredictable
(e) none of the above.
Ans: c

113. In hydrodynamic bearings
(a) the oil film pressure is generated only by the rotation of the journal
(b) the oil film is maintained by supplying oil under pressure
(c) do not require external supply of lubricant
(d) grease is used for lubrication
(e) none of the above.
Ans: a

114. Antifriction bearings are
(a) sleeve bearings
(b) hydrodynamic bearings
(c) thin lubricated bearings
(d) ball and roller bearings
(e) none of the above.
Ans: e

115. If p = bearing pressure on projected bearing area, z = absolute viscosity of lubricant, and N = speed of journal, then the bearing characteristic number is given by
(a) ZN/p
(b) p/ZN
(c) Z/pN
(d) N/Zp
(e) Zp/N.
Ans: a

116. The usual clearance provided in hydrodynamic bearing per mm of diameter of shaft is
(a) 0.01 micron
(b) 0.1 micron
(c) 1 micron
(d) 10 microns
(e) 25 microns.
Ans: c

117. In hydrostatic bearings
(a) the Oil film pressure is generated only by the rotation of the journal
(b) the oil film is maintained by supplying oil under pressure
(c) do not require external supply of lubricant
(d) grease is used for lubrication
(e) none of the above.
Ans: b

118. Oil in journal bearing should be applied at the point where load is
(a) nil or lightest
(b) maximum
(c) average
(d) any one of the above
(e) unpredictable.
Ans: a

119. The rated life of a bearing varies
(a) directly as load
(b) inversely as square of load
(c) inversely as cube of load
(d) inversely as fourth power of load
(e) none of the above.
Ans: c

120. In oilness bearings
(a) the oil film pressure is generated only by the rotation of the journal
(b) the oil film is maintained by supplying oil under pressure
(c) do not require external supply of lubricant
(d) grease required to be applied after some intervals
(e) none of the above.
Ans: c

121. In V-belt drive, belt touches
(a) at bottom
(b) at sides only
(c) both at bottom and sides
(d) could touch anywhere
(e) none of the above.
Ans: b

122. Three different weights fall from a certain height under vacuum. They will take
(a) same time to reach earth
(b) times proportional to weight to reach earth
(c) times inversely proportional to weight to reach earth
(d) unpredictable
(e) none of the above.
Ans: a

123. In cross or regular lay ropes
(a) direction of twist of wires in strands is opposite to the direction of twist of strands
(b) direction of twist of wires and strands are same
(c) wires in two adjacent strands are twisted in opposite direction
(d) wires are not twisted
(e) none of the above.
Ans: a

124. In standard taper roller bearings, the angle of taper of outer raceway is
(a) 5°
(b) 8°
(c) 15°
(d) 25°
(e) 40°.
Ans: d

125. In composite or reverse laid ropes
(a) direction of twist of wires in strands is opposite to the direction of twist of strands
(b) direction of twist of wires and strands are same
(c) wires in two adjacent strands are twisted in opposite direction
(d) wires are not twisted
(e) none of the above.
Ans: c

126. Whether any core is required in wire ropes
(a) yes
(b) no
(c) sometimes
(d) rarely
(e) very often.
Ans: a

127. If shearing stress in nut is half the tensile stress in a bolt, then nut length should be equal to
(a) diameter of bolt
(b) 0.75 x diameter of bolt
(c) 1.25 x diameter of bolt
(d) 1.5 x diameter of bolt
(e) 0.5 x diameter of bolt.
Ans: a

128. Basic shaft is one
(a) whose upper deviation is zero
(b) whose lower deviation is zero
(c) whose lower as well as upper deviations are zero
(d) does not exist
(e) none of the above.
Ans: a

129. Basic hole is one
(a) whose upper deviation is zero
(b) whose lower deviation is zero
(c) whose lower as well as upper deviations are zero
(d) does not exist
(e) none of the above.
Ans: b

130. I.S. specifies following total number of grades of tolerances
(a) 18
(b) 16
(c) 20
(d) 22
(e) 14.
Ans: a

131. For standard coarse threads of nut, the threads will be as strong in failure by shear as the bolt in tension, if the height of nut (h) is approximately
(a) 0.4 times
(b) 0.6 times
(c) 0.7 times
(d) 0.8 times
(e) 0.9 times the normal diameter of bolt.
Ans: a

132. Allen bolts are
(a) self locking bolts
(b) designed for shock load
(c) used in aircraft application
(d) provided with hexagonal depression in head
(e) uniform strength bolts.
Ans: d

133. The resultant axial load on a bolt depends on
(a) initial tension
(b) external load applied
(c) relative elastic yielding (springness) of the bolt and the connected member
(d) (a) and (b) above
(e) (a), (b) and (c) above.
Ans: e

134. The connecting rod bolts are tightened up so that tightening stress
(a) is just sufficient to hold parts together
(b) approaches yield point
(c) is 50% of yield point
(d) is about yield point divided by safety factor
(e) none of the above.
Ans: b

135. The connecting rod bolts are tightened up with initial tension greater than the external load so that
(a) joint may not open up
(b) bolts are weakest elements
(c) the resultant load on the bolt would not be affected by the external cyclic load
(d) bolts will not loosen during service
(e) none of the above.
Ans: c

136. If an application calls for stresses on screw threads in one direction only, then the following type of thread would be best suited
(a) square
(b) acme
(c) buttress
(d) BSW
(e) metric.
Ans: c

137. When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at
(a) shank
(c) in the middle
(d) at the thread
(e) anywhere in the bolt.
Ans: d

138. The shock absorbing capacity of a bolt can be increased by
(a) tightening it properly
(b) increasing shank diameter
(c) grinding the shank
(d) using washer
(e) making shank diameter equal to core diameter of thread.
Ans: e

Machine Design MCQ : Part 1 | Part 2 | Part 3 | Part 4

###### Mechanical Subjectwise Basic Concept Notes ,Articles

Sachin Thorat

Sachin is a B-TECH graduate in Mechanical Engineering from a reputed Engineering college. Currently, he is working in the sheet metal industry as a designer. Additionally, he has interested in Product Design, Animation, and Project design. He also likes to write articles related to the mechanical engineering field and tries to motivate other mechanical engineering students by his innovative project ideas, design, models and videos.

## One thought on “Machine Design MCQ Objective Question and Answers Part 4”

1. ERIC FANG ATEGHA says:

Sir the studies are good

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