141. A flange coupling is used to connect two shafts
which are perfectly aligned
which are not in exact alignment
have lateral misalignment
whose axes intersect a
✅ The correct answer is option A.
Machine Design MCQs
142. The efficiency of a square threaded screw is maximum if the helix angle is equal to (where φ = Angle of friction)
90° – φ
45° – φ
45° – φ/2
45° + φ/2
✅ The correct answer is option C.
143. The angle of twist of shaft is
directly proportional to (shaft diameter)2
inversely proportional to (shaft diameter)2
directly proportional to (shaft diameter)4
inversely proportional
✅ The correct answer is option D.
144. The largest diameter of an external or internal screw thread is known as
minor diameter
major diameter
pitch diameter
none of these
✅ The correct answer is option B.
145. When bevel gears having equal teeth and equal pitch angles connect two shafts whose axes intersect at right angle, then they are known as
angular bevel gears
crown bevel gears
internal bevel gears
mitre gears
✅ The correct answer is option D.
146. In designing a key, it is assumed that the distribution of forces along the length of key
varies linearly
is uniform throughout
varies exponentially, being more at the torque-input end
varies exponentially,
✅ The correct answer is option B.
147. 18/8 steel contains
18% nickel and 8% chromium
18% chromium and 8% nickel
18% nickel and 8% vanadium
18% vanadium and 8% ni
✅ The correct answer is option B.
148. A bolt is designed on the basis of __________ with a large factor of safety.
direct tensile stress
direct compressive stress
direct bending stress
direct shear stress
✅ The correct answer is option A.
149. A long helical spring having a spring stiffness of 12 kN/m and number of turns 20, breaks into two parts with number of turns 10 each in both the parts. If the two parts are connected in series, then the softness of the resultant spring will be
6 kN/m
12 kN/m
24 kN/m
30 kN/m
✅ The correct answer is option B.