CTET - Theory of Machines 1000+ MCQ [Solved] PDF Download

1. The pitching of a ship produces forces on the bearings which act __________ to the motion of the ship.
A. Vertically and parallel
B. Vertically and perpendicular
C. Horizontally and parallel
D. Horizontally and perpendicular
Answer : D

2. Hammer blow
A. Is the maximum horizontal unbalanced force caused by the mass provided to balance the reciprocating masses.
B. Is the maximum vertical unbalanced force caused by the mass added to balance the reciprocating masses
C. Varies as the square root of the speed
D. Varies inversely with the square of the speed
Answer : B

3. Creep in belt drive is due to
A. Weak material of the belt
B. Weak material of the pulley
C. Uneven extensions and contractions of the belt when it passes from tight side to slack side
D. Expansion of the belt
Answer : C

4. Throw of a cam is the maximum distance of the follower from
A. Base circle
B. Pitch circle
C. Root circle
D. Prime circle
Answer : A

5. The motion between a pair which takes place in __________ is known as incompletely constrained motion.
A. One direction only
B. Two directions only
C. More than one direction
D. None of these
Answer : C

6. The maximum fluctuation of energy is the
A. Difference between the maximum and minimum energies
B. Sum of the maximum and minimum energies
C. Variations of energy above and below the mean resisting torque line
D. Ratio of the mean resisting torque to the workdone per cycle
Answer : A

7. Which of the following is a higher pair?
A. Belt and pulley
B. Turning pair
C. Screw pair
D. Sliding pair
Answer : A

8. The frictional torque transmitted in a conical pivot bearing with assumption of uniform pressure is __________ as compared to uniform wear.
A. Less
B. More
C. Same
D. None of these
Answer : B

9. The size of cam depends upon
A. Base circle
B. Pitch circle
C. Prime circle
D. Pitch curve
Answer : A

10. The direction of Coriolis component of acceleration is the direction
A. Of relative velocity vector for the two coincident points rotated by 90° in the direction of the angular velocity of the rotation of the link
B. Along the centripetal acceleration
C. Along tangential acceleration
D. Along perpendicular to angular velocity
Answer : A

11. The contact ratio is given by
A. (Length of the path of approach)/(Circular pitch)
B. (Length of path of recess)/(Circular pitch)
C. (Length of the arc of contact)/(Circular pitch)
D. (Length of the arc of approach)/cos?
Answer : C

12. A spring controlled governor is said to be stable if the controlling force line when produced intersects the Y-axis
A. At the origin
B. Below the origin
C. Above the origin
D. Any one of these
Answer : B

13. The relation between number of pairs (p) forming a kinematic chain and the number of links (l) is
A. l = 2p - 2
B. l = 2p - 3
C. l = 2p - 4
D. l = 2p - 5
Answer : C

14. The radial distance of a tooth from the pitch circle to the bottom of the tooth is called
A. Dedendum
B. Addendum
C. Clearance
D. Working depth
Answer : A

15. In S.H.M., acceleration is proportional to
A. Velocity
B. Displacement
C. Rate of change of velocity
D. All of the above
Answer : B

16. The Hooke's joint consists of:
A. Two forks
B. One fork
C. Three forks
D. Four forks
Answer : A

17. A reed type tachometer use the principle of
A. Longitudinal vibration
B. Torsional vibration
C. Transverse vibration
D. Damped free vibration
Answer : C

18. If two moving elements have surface contact in motion, such pair is known as
A. Sliding pair
B. Rolling pair
C. Surface pair
D. Higher pair
Answer : D

19. In a turning moment diagram, the variations of energy above and below the mean resisting torque line is called
A. Fluctuation of energy
B. Maximum fluctuation of energy
C. Coefficient of fluctuation of energy
D. None of these
Answer : A

20. When two links are connected by a pin joint, their instantaneous centre lies
A. On their point of contact
B. At the centre of curvature
C. At the centre of circle
D. At the pin joint
Answer : D

21. In a four stroke I.C. engine, the turning moment during the compression stroke is
A. Positive throughout
B. Negative throughout
C. Positive during major portion of the stroke
D. Negative during major portion of the stroke
Answer : B

22. In gramophones for adjusting the speed of the turntable, the following type of governor is commonly employed
A. Hartung governor
B. Wilson Hartnell governor
C. Pickering governor
D. Inertia governor
Answer : C

23. Longitudinal vibrations are said to occur when the particles of a body moves
A. Perpendicular to its axis
B. Parallel to its axis
C. In a circle about its axis
D. None of these
Answer : B

24. In S.H.M., the velocity vector w.r.t. displacement vector
A. Leads by 90°
B. Lags by 90°
C. Leads by 180°
D. Are in phase
Answer : A

25. The maximum frictional force, which comes into play, when a body just begins to slide over the surface of the other body, is known as
A. Static friction
B. Dynamic friction
C. Limiting friction
D. Coefficient of friction
Answer : C

26. A rigid body, under the action of external forces, can be replaced by two masses placed at a fixed distance apart. The two masses form an equivalent dynamical system, if
A. The sum of the two masses is equal to the total mass of body
B. The centre of gravity of the two masses coincides with that of the body
C. The sum of mass moment of inertia of the masses about their centre of gravity is equal to the mass moment of inertia of the body
D. All of the above
Answer : D

27. Under logarithmic decrement, the amplitude of successive vibrations are
A. Constant
B. In arithmetic progression
C. In geometric progression
D. In logarithmic progression
Answer : C

28. The D-slide valve is also known as
A. Inside admission valve
B. Outside admission valve
C. Piston slide valve
D. None of these
Answer : B

29. The frictional torque transmitted in a flat collar bearing, considering uniform pressure, is (where r? and r? = External and internal radii of collar respectively)
A. (1/2). ? W (r? + r?)
B. (2/3). ? W (r? + r?)
C. (1/2). ? W [(r?³ - r?³)/(r?² - r?²)]
D. (2/3). ? W [(r?³ - r?³)/(r?² - r?²)]
Answer : D

30. The sensitiveness of the governor __________ as the speed range decreases.
A. Remains unaffected
B. Decreases
C. Increases
D. None of these
Answer : C

31. The Grubler's criterion for determining the degrees of freedom (n) of a mechanism having plane motion is (where l = Number of links, and j = Number of binary joints)
A. n = (l -1) - j
B. n = 2(l - 1) - 2j
C. n = 3(l - 1) - 2j
D. n = 4(l - 1) - 3j
Answer : C

32. Length of arc of contact is given by
A. Arc of approach - Arc of recess
B. Arc of approach + Arc of recess
C. Arc of approach / Arc of recess
D. Arc of approach × Arc of recess
Answer : B

33. Which of the following mechanisms produces mathematically an exact straight line motion?
A. Grasshopper mechanism
B. Watt mechanism
C. Peaucellier's mechanism
D. Tchebicheff mechanism
Answer : C

34. The product of the diametral pitch and circular pitch is equal to
A. 1
B. 1/?
C. ?
D. 2 ?
Answer : C

35. The magnitude of velocities of the points on a rigid link is
A. Directly proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre
B. Directly proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre
C. Inversely proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre
D. Inversely proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre
Answer : D

36. The mechanism consisting of three turning pairs and one sliding pair, is called a
A. Single slider crank chain
B. Whitworth quick return motion mechanism
C. Crank and slotted lever quick return motion mechanism
D. All of the above
Answer : D

37. In its simplest form, a cam mechanism consists of following number of links
A. 1
B. 2
C. 3
D. 4
Answer : C

38. A disc is a spinning with an angular velocity ? rad/s about the axis of spin. The couple applied to the disc causing precession will be (where I = Mass moment of inertia of the disc, and ?P = Angular velocity of precession of the axis of spin)
A. (1/2).I?²
B. I?²
C. (1/2). I ? ?_P
D. I ? ?_P
Answer : D

39. When the pitching of a ship is __________ the effect of gyroscopic couple acting on it will be to move the ship towards port side.
A. Upward
B. Downward
C. Forward
D. Backward
Answer : B

40. Maximum fluctuation of energy in a flywheel is equal to [where I = Mass moment of inertia of the flywheel, E = Maximum fluctuation of energy, CS = Coefficient of fluctuation of speed, and ? = Mean angular speed = (?? + ??)/2]
A. I.?.(?? - ??)
B. I.?².C_S
C. 2.E.C_S
D. All of these
Answer : D

41. A rotary internal combustion engine has __________ cylinders.
A. Four
B. Five
C. Six
D. Seven
Answer : D

42. The type of coupling used to join two shafts whose axes are neither in same straight line nor parallel, but intersect is
A. Flexible coupling
B. Universal coupling
C. Chain coupling
D. Oldham's coupling
Answer : B

43. The mechanism forms a structure, when the number of degrees of freedom (n) is equal to
A. 0
B. 1
C. 2
D. -1
Answer : A

44. In a multiple V-belt drive, if one of the belts is broken, then we should replace
A. The broken belt only
B. All the belts
C. The broken belt and the belts on either side of it
D. None of the above
Answer : B

45. A shaft has two heavy rotors mounted on it. The transverse natural frequencies, considering each of the rotor separately, are 100 Hz and 200 Hz respectively. The lowest critical speed is
A. 5,367 r.p.m.
B. 6,000 r.p.m.
C. 9,360 r.p.m.
D. 12,000 r.p.m.
Answer : A

46. When the primary direct crank of a reciprocating engine makes an angle of ? with the line of stroke, then the secondary direct crank will make an angle of _________ with the line of stroke.
A. ?/2
B. ?
C. 2?
D. 4?
Answer : C

47. The relative velocity of B with respect to A in a rigid link AB is
A. Parallel to AB
B. Perpendicular to AB
C. Along AB
D. At 45° to AB
Answer : B

48. Minimum number of teeth for involute rack and pinion arrangement for pressure angle of 20° is
A. 18
B. 20
C. 30
D. 34
Answer : A

49. In a spring controlled governor, when the controlling force ________ as the radius of rotation increases, it is said to be a stable governor.
A. Remains constant
B. Decreases
C. Increases
D. None of these
Answer : C

50. A thin circular disc is rolling with a uniform linear speed, along a straight path on a plane surface. Which of the following statement is correct in this regard?
A. All points of the disc have the same velocity
B. The centre of the disc has zero acceleration
C. The centre of the disc has centrifugal acceleration
D. The point on the disc making contact with the plane surface has zero acceleration
Answer : B