101. The lead angle of a worm is 22.5°. Its helix angle will be
22.5°
45°
67.5°
90°
✅ The correct answer is option C.
Machine Design MCQs
102. The temperature at which the new grains are formed in the metal is known as
lower critical temperature
upper critical temperature
recrystallisation temperature
none of these
✅ The correct answer is option C.
103. The thickness of key is usually taken equal to one-sixth of diameter of shaft.
Yes
No
✅ The correct answer is option A.
104. An open coiled helical compression spring ‘A’ of mean diameter 50 mm is subjected to an axial load W. Another spring ‘B’ of mean diameter 25 mm is similar to spring ‘A’ in all respects. The deflection of spring ‘B’ will be __________ as compared to spring ‘A’.
one-eighth
one-fourth
one-half
double
✅ The correct answer is option A.
105. A special case of ductility which permits materials to be rolled or hammered into thin sheets, is called
plasticity
elasticity
ductility
malleability
✅ The correct answer is option D.
106. If the centre distance of the mating gears having involute teeth is increased, then the pressure angle
increases
decreases
remains unchanged
✅ The correct answer is option A.
107. Rankine’s theory is used for
brittle materials
ductile materials
elastic materials
plastic materials
✅ The correct answer is option A.
108. A saddle key __________ power through frictional resistance only.
transmits
does not transmit
✅ The correct answer is option A.
109. A double strap butt joint (with equal straps) is
always in single shear
always in double shear
either in single shear or double shear
any one of these
✅ The correct answer is option B.
110. For a square key made of mild steel, the shear and crushing strength are related as
shear strength is equal to crushing strength
shear strength is greater than crushing strength
shear strength is less than crushing strength
none of the above
✅ The correct answer is option A.