Theory of Machines

ME4I

22438

Multiple Choice Questions (MCQs)

1   Choose correct option related to need of acceleration analysis
(A)   significant role in development of machine and mechanism
(B)   forces on the link can be calculated
(C)   forms basis the basis for stress analysis of mechanism
(D)   all of the above

2   A SI unit of linear velocity and angular velocity respectively are —–
(C)   m/sec

3   —– is the velocity of point B of link AB, if length of link AB is 35mm and angular velocity is 50 rad/sec
(A)   1.75 mm/sec
(B)   1.75 m/sec
(C)   17.5 m/sec
(D)   1750 m/sec

4   The velocity of particle with respect to a fixed point is called —–
(A)   relative velocity
(B)   absolute velocity
(C)   relative acceleration
(D)   angular acceleration

5   The component of acceleration parallel to the link is called —–.
(B)   Tangential
(C)   Coriolis
(D)   Absolute

6   In velocity triangle the “Vco1” indicates
(A)   Velocity of fixed point O2 w.r.t. C
(B)   Velocity of fixed point O1 w.r.t. C
(C)   Velocity of C w.r.t. fixed point O2
(D)   Velocity of C w.r.t. fixed point O1

7   Velocity of crank in the slider crank mechanism when length of crank is 75mm and crank rotates at 60 r.p.m is —–.
(A)   0.471 mm/sec
(B)   4.5 m/sec
(C)   4500 mm/sec
(D)   0471 m/sec

8   By dividing the tangential component of acceleration with length of link we get —–.
(D)   above options are incorrect

9   Radial component and tangential components are two components of the acceleration of a particle at any instant will be —–
(A)   parallel to each other
(B)   opposite to each other
(C)   inclined at 45 degrees
(D)   all above are incorrect

10   Theory of machine is classified as —.
(A)   Kinematics
(B)   Statics
(C)   Kinetics
(D)   All of above

11   Following are the types of links
(A)   Rigid
(B)   Flexible
(C)   Fluid
(D)   All of above

12   Following l, s, p and q are the example of —.
(D)   None of above

13   Following kinematic chain having total —– number of links
(A)   2
(B)   4
(C)   5
(D)   6

14   Following mechanism having —– number of ternary joints
(A)   1
(B)   2
(C)   3
(D)   4

15   Following pair forms —.
(A)   Lower pair
(B)   Higher pair
(C)   Lower as well as higher pair
(D)   None of the above options

16   Following pair (cam and follower) is an example of —–.
(A)   Closed pair or self-closed
(B)   Unclosed pair
(C)   above two options are incorrect
(D)   None of the above options

17   Following is an example of —–
(A)   Completely constrained motion
(B)   incompletely constrained motion
(C)   Successfully constrained motion
(D)   None of above

18   one of the following statements is incorrect
(A)   Grashoff’s rule states that for a planar crank-rocker 4-bar mechanism, the sum of the shortest and longest link lengths cannot be less than the sum of the remaining two link lengths.
(B)   Inversions of a mechanism are created by fixing different links of kinematic chain, one at a time.
(C)   Geneva mechanism is an intermittent motion device.
(D)   Grubler’s criterion assumes mobility of a planar mechanism to be one.

19   Following of the mechanism is used to convert rotary motion into reciprocating motion
(A)   Elliptical trammel
(B)   Geneva mechanism
(C)   Scotch yoke mechanism
(D)   Oscillating cylinder engine

20   Following of the option is not an inversion four bar chain mechanism
(A)   Coupled wheel of locomotive
(B)   Oldham’s coupling
(C)   Pantograph
(D)   Watt straight line indicator mechanism

21   Following is the equation for Grubler’s criterion for plane mechanisms with constrained motion
(A)   3n-2j1-4=0
(B)   3n-3j1-4=0
(C)   3n+2j1+4=0
(D)   3n+3j1+4=0

22   A chain comprises of 5 links having 5 joints. Is it kinematic chain?
(A)   it is a kinematic chain
(B)   it is not a kinematic chain
(C)   It is a marginal case
(D)   None of the mentioned

23   Following is the displacement diagram for —–. of follower
(A)   Uniform velocity
(B)   SHM
(C)   Uniform acceleration and retardation
(D)   sinusoidal

24   Following sentence is not correct related to pitch curve
(A)   For roller follower pitch curve is greater than base circle by radius of roller of follower
(B)   For roller follower pitch curve and base circle are same in size
(C)   For knife edge follower pitch curve and base circle are same in size
(D)   Given above options are all correct

25   Size of the cam depend on —– of cam
(A)   Prime circle
(B)   Pitch circle
(C)   Base circle
(D)   All of above

26   Radial Cam in which follower —–
(A)   In a direction perpendicular to the cam axis
(B)   In a direction parallel to the cam axis
(C)   In any direction irrespective of the cam axis
(D)   Along the cam axis

27   Following is a —– type of follower
(A)   Translating
(B)   Reciprocating
(C)   above two options are incorrect
(D)   above two options are correct

28   The main limitation of —– cam is that it has to reverse the direction to reset the position of the follower
(A)   Spiral cam
(B)   Wedge cam
(C)   Globoidal cam
(D)   Spherical cam

29   In a cone pulley, if the sum of radii of the pulleys on the driving and driven shafts is constant, then_____
(A)   Cross belt drive is preferred
(B)   Open belt drive is preferred
(C)   Both of above
(D)   None of above

30   Two pulleys, one 800 mm diameter and the other 600 mm diameter are mounted on parallel shafts 5 m apart and are connected by a belt drive. Find the length of the belt required for cross belt drive.
(A)   12.201 m
(B)   12.397 m
(C)   12.297 m
(D)   12.301m

31   Two pulleys of diameters d1 and d2 and at distance x apart are connected by means of an open belt drive. The length of the belt drive is____
(A)   π/2(d1+d2) +2x(d12-d22)/4x
(B)   π/2(d1+d2) +2x(d12+d22)/4x
(C)   π/2(d1-d2) +2x(d12-d22)/4x
(D)   π/2(d1-d2) +2x(d12+d22)/4x

32   An engine shaft running at 180 r.p.m. is required to drive machine shaft by means of a belt. The pulley on the engine shaft is of 2 meter in dia. and that of machine shaft is 1 meter in dia. Determine the speed of machine shaft.
(A)   300 r.p.m.
(B)   320 r.p.m.
(C)   360 r.p.m.
(D)   90 r.p.m.

33   When the belt is stationary, it is subjected to some tension, known as initial tension. The value of this tension is equal to the _____
(A)   tension in the tight side of the belt
(B)   tension in the slack side of the belt
(C)   average tension of the tight side and slack side of the belt
(D)   sum of the tensions in the tight side and slack side of the belt

34   In chain drive, constant velocity ratio is observed to some extent because of _______
(A)   there is no slip
(B)   center to center distance between two shafts is short
(C)   lubrication is provided
(D)   All of above

35   The number of links of the chain should be always ______
(A)   Multiple of 3
(B)   Even
(C)   Odd
(D)   None of above

36   Which of the following gears should be recommended for a speed reduction 50:1?
(A)   Differential
(B)   Spur
(C)   Bevel
(D)   Worm and worm wheel

37   _____ gears are used in a differential of an automobile vehicle.
(A)   Double helical
(B)   Spur
(C)   Helical bevel
(D)   Bevel

38   According to law of gearing, which sentence is correct of the following.
(A)   Clearance between mating teeth should be provided
(B)   Teeth should be of involute type
(C)   Teeth should be of cycloidal type
(D)   None of above

39   In simple gear train, if the number of idle gears is even, then the direction of motion of driven gear will be____
(A)   Same as that driving gear
(B)   Opposite that of driving gear
(C)   Depends upon the number of teeth on the driving gear
(D)   Depends upon the number of teeth on the driven gear

40   In a simple band brake, the angle of contact is 210 degree and coefficient of friction is 0.35. If the brake drum is 180mm in diameter and maximum permissible tension in band is 3200 N, Find Braking torque. if N=460 r.p.m.
(A)   TB=208.15
(B)   TB=209.01
(C)   TB=208.30
(D)   None of above

41   If x ≤ µ.a, then we can say the condition is ________
(A)   Self-energizing brake
(B)   Disc brake
(C)   Self-locking
(D)   Drum brake

42   If moment of actuating force and moment of frictional force are acting in the same direction but different in magnitude, then it is known as _______
(A)   Self-locking brake
(B)   Drum brake
(C)   Internal expanding brake
(D)   Self-energizing

43   Double block or shoe brakes used to reduce _______
(A)   Unbalanced force on the shaft
(B)   Vibration of the shaft
(C)   All of above
(D)   None of above

44   Hydraulic braking systems works on _______ Principle.
(A)   Law of energy conservation
(B)   Law of mass conservation
(C)   Pascal’s law
(D)   Newton law

45   If drum rotates in clockwise direction in case of single block brake, braking torque will be __
(A)   TB=μ p l r / x
(B)   TB=μ p r s / z
(C)   TB=μ p l r / z
(D)   None of above

46   If vehicle is moving on the inclined surface of road in the upward direction, then we can say that, the clutch is _________
(A)   Disengaged
(B)   Centrifugal
(C)   Old
(D)   Engaged

47   Uniform pressure theory applicable for _________
(A)   Old clutch
(B)   Worn out clutch
(C)   New clutch
(D)   All of above

48   In diaphragm clutch, a diaphragm spring is used_____
(A)   To produce required pressure for engagement
(B)   To replace the coil spring
(C)   Both of above
(D)   None of above

49   Which of the following is function of flywheel?
(A)   Store and release energy during work cycle
(B)   Reduce power capacity of the electric motor
(C)   Reduce amplitude of speed fluctuations
(D)   All of the above

50   In a turning moment diagram, the variations of energy above and below the mean resisting torque line is called
(A)   Maximum fluctuation of energy
(B)   Coefficient of fluctuation of energy
(C)   Fluctuation of energy
(D)   All of the above

51   Which of the following is not true for cast iron flywheels?
(A)   Given complex shape
(B)   Sudden failure
(C)   Excellent damping
(D)   Cheap

52   Which device is used to regulate the mean speed of engine, over a duration, during which, load on engine varies?
(A)   Governors
(B)   Flywheel
(C)   Gear
(D)   Clutches

53   Which of the following is a spring-controlled governor?
(A)   Hartung
(B)   Hartnell
(C)   Pickering
(D)   All of the above

54   If speed of the engine fluctuates continuously above and below the mean speed, then a governor is said to be __________.
(A)   Unstable
(B)   Hunt
(C)   Stable
(D)   Isochronous

55   The primary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is _________
(A)   0 deg
(B)   90 deg
(C)   180 deg
(D)   360 deg

56   Two masses A and B are attached to a shaft revolve in the same plane. The masses are 12kg and 10kg and their radii of rotation are 40mm and 50mm respectively. Calculate centrifugal force exerted by each rotating mass on shaft?
(A)   0.50 kg.m. and 0.6 kg.m.
(B)   1.08 kg.m. and 45 kg.m.
(C)   0.48 kg.m. and 0.5 kg.m.
(D)   0.5 kg.m. and 0.48 kg.m.