Machine Design MCQ
SET-2
21. The velocity of sliding __________ the distance of the point of contact from the pitch point.
- A. is directly proportional to
- B. is inversely proportional to
- C. is equal to cos φ multiplied by
- D. does not depend upon
Answer: A
22. A column is known as a long column if the slenderness ratio is
- A. 40
- B. 50
- C. 70
- D. 100
Answer: D
23. Circumferential joint in boilers is used to get the required length of a boiler.
- A. True
- B. False
Answer: A
24. The ball bearings are provided with a cage
- A. to reduce friction
- B. to facilitate slipping of balls
- C. to prevent the lubricant from flowing out
- D. to maintain the balls at a fixed distance apart
Answer: D
25. When screw threads are to be used in a situation where power is being transmitted in one direction only, then the screw threads suitable for this will be
- A. square threads
- B. acme threads
- C. knuckle threads
- D. buttress threads
Answer: D
26. In radial cams, the follower moves
- A. in a direction perpendicular to the cam axis
- B. in a direction parallel to the cam axis
- C. in any direction irrespective of cam axis
- D. along the cam axis
Answer: A
27. The square threads are not so strong as V-threads but they offer less frictional resistance to motion than Whitworth threads.
- A. Correct
- B. Incorrect
Answer: A
28. According to Unwin’s formula, the relation between the diameter of rivet hole (d) and the thickness of plate (t) is given by (where d and t are in mm)
- A. d = t
- B. d = 1.6 t
- C. d = 2 t
- D. d = 6 t
Answer: D
29. In order to avoid tearing of the plate at an edge, the distance from the centre line of the rivet hole to the nearest edge of the plate should be equal to (where d = Diameter of rivet hole)
- A. d
- B. 1.5 d
- C. 2 d
- D. 2.5 d
Answer: B
30. The value of stress concentration factor depends upon
- A. material of the part
- B. geometry of the part
- C. material and geometry of the part
- D. none of these
Answer: C
31. Which of the following material has the maximum ductility?
- A. Mild steel
- B. Copper
- C. Zinc
- D. Aluminium
Answer: A
32. When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at the
- A. head
- B. shank
- C. thread
- D. middle
Answer: C
33. In order to obtain the bolts of uniform strength, an axial hole is drilled through the head as far as the threaded portion such that the area of shank becomes equal to the root area of the thread.
- A. True
- B. False
Answer: A
34. An open belt drive is used when
- A. shafts are arranged parallel and rotate in the opposite directions
- B. shafts are arranged parallel and rotate in the same directions
- C. shafts are arranged at right angles and rotate in one definite direction
- D. driven shaft is to be started or stopped whenever desired without interferring with the driving shaft
Answer: B
35. In unilateral system of tolerance, the tolerance is allowed on
- A. one side of the actual size
- B. one side of the nominal size
- C. both sides of the actual size
- D. both sides of the nominal size
Answer: B
36. The constant factor in case of R10 series of preferred numbers is
- A. 1.06
- B. 1.12
- C. 1.26
- D. 1.58
Answer: C
37. The pipe joint mostly used for pipes carrying water at low pressures is
- A. socket joint
- B. nipple joint
- C. union joint
- D. spigot and socket joint
Answer: A
38. According to Guest’s theory, the failure occurs at a point in a member when the maximum shear stress in a bi-axial stress system reaches the shear stress at elastic limit in simple tension test.
- A. True
- B. False
Answer: A
39. For maximum power, the velocity of the belt will be
Answer: C
40. Surface endurance limit of gear material is dependent upon its
- A. elastic strength
- B. yield strength
- C. brinell hardness number
- D. toughness
Answer: C