If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the latter at the same speed will be

one and a half times the first one

For dynamic balancing of a shaft

the net dynamic force acting on the shaft is equal to zero

the net couple due to the dynamic forces acting on the shaft is equal to zero

Which of the following is a turning pair?

Piston and cylinder of a reciprocating steam engine

Shaft with collars at both ends fitted into a circular hole

Which of the following property of the instantaneous centre is correct ?

A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.

The two rigid links have no linear velocity relative to each other at the instantaneous centre.

The velocity of the instantaneous centre relative to any third rigid link is same whether the instantaneous centre is regarded as a point on the first rigid link or on the second rigid link.

The frictional torque transmitted by a disc or plate clutch is same as that of

truncated conical pivot bearing

220 + Mcqs in Theory of machines in Mechanical Engineering Page 1 McqOptions

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» E.

Discussion

2.	At the node, the shaft remains unaffected by the vibration.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

3.	When the two elements of a pair have __________ when in motion, it is said to a lower pair.
A.	line or point contact
B.	surface contact
Answer» C.

Discussion

4.	The tractive force is maximum or minimum when the angle of inclination of crank with the line of stroke (θ) is equal to
A.	0° and 90°
B.	90° and 180°
C.	135° and 315°
D.	270° and 360°
Answer» C. 135° and 315°

Discussion

5.	A point on a connecting link (excluding end points) of a double slider crank mechanism traces a
A.	straight line path
B.	hyperbolic path
C.	parabolic path
D.	elliptical path
Answer» E.

Discussion

6.	The natural frequency of free torsional vibrations of a shaft is equal to (where = Torsional stiffness of the shaft, and = Mass moment of inertia of the disc attached at the end of a shaft)
A.	2π
Answer» D.

Discussion

7.	If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the latter at the same speed will be
A.	four times the first one
B.	same as the first one
C.	one fourth of the first one
D.	one and a half times the first one
Answer» D. one and a half times the first one

Discussion

8.	A slider moving on a fixed link having constant radius of curvature will have its instantaneous centre at the centre of the circle.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

9.	According to Kennedy's theorem, if three bodies move relatively to each other, their instantaneous centres will lie on a
A.	straight line
B.	parabolic curve
C.	triangle
D.	rectangle
Answer» B. parabolic curve

Discussion

10.	The periodic time is given by (where ω = Angular velocity of the particle in rad/s)
A.	ω/2π
B.	2π/ω
C.	ω x 2π
D.	π/ω
Answer» C. ω x 2π

Discussion

11.	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» E.

Discussion

12.	If ω/ω is very high for a body vibrating under steady state vibrations, the phase angle for all values of damping factors, will tend to approach
A.	0°
B.	90°
C.	180°
D.	360°
Answer» D. 360°

Discussion

13.	When the relation between the controlling force () and radius of rotation () for a spring controlled governor is = + , then the governor will be
A.	stable
B.	unstable
C.	isochronous
D.	none of these
Answer» C. isochronous

Discussion

14.	In vibration isolation system, the transmissibility will be equal to unity, for all values of damping factor, if ω/ω is
A.	equal to one
B.	equal to
C.	less than
D.	greater than
Answer» C. less than

Discussion

15.	If ω/ω = , where co is the frequency of excitation and ω is the natural frequency of vibrations, then the transmissibility of vibration will the
A.	0.5
B.	1
C.	1.5
D.	2
Answer» C. 1.5

Discussion

16.	A disturbing mass m1 attached to the rotating shaft may be balanced by a single mass attached in the same plane of rotation as that of , such that (where and are the radii of rotation of and respectively)
A.	=
B.	=
C.	=
D.	none of these
Answer» C. =

Discussion

17.	When a particle moves round the circumference of a circle of radius with ω rad/s, then its maximum acceleration is ω.
A.	Right
B.	Wrong
Answer» B. Wrong

Discussion

18.	The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (θ) is equal to
A.	90° and 180°
B.	45° and 225°
C.	180° and 270°
D.	270° and 360°
Answer» C. 180° and 270°

Discussion

19.	The two elements of a pair are said to form a __________ when they permit relative motion between them.
A.	open pair
B.	kinematic pair
Answer» C.

Discussion

20.	The Whitworth quick return motion mechanism is formed in a slider crank chain when the
A.	coupler link is fixed
B.	longest link is a fixed link
C.	slider is a fixed link
D.	smallest link is a fixed link
Answer» B. longest link is a fixed link

Discussion

21.	The secondary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is
A.	0° and 90°
B.	180° and 360°
C.	both (a) and (b)
D.	none of these
Answer» D. none of these

Discussion

22.	For dynamic balancing of a shaft
A.	the net dynamic force acting on the shaft is equal to zero
B.	the net couple due to the dynamic forces acting on the shaft is equal to zero
C.	both (a) and (b)
D.	none of the above
Answer» D. none of the above

Discussion

23.	When two pulleys are connected by means of an open belt drive, then both the pulleys will rotate is opposite directions.
A.	Right
B.	Wrong
Answer» C.

Discussion

24.	A mechanism consisting of four links is called a __________ mechanism.
A.	simple
B.	compound
Answer» B. compound

Discussion

25.	The amplitude of vibration is always __________ the radius of the circle.
A.	equal to
B.	less than
C.	greater than
Answer» B. less than

Discussion

26.	In vibration isolation system, if ω/ω > 1, then the phase difference between the transmitted force and the disturbing force is
A.	0°
B.	90°
C.	180°
D.	270°
Answer» D. 270°

Discussion

27.	A very sensitive governor will cause hunting.
A.	True
B.	False
Answer» B. False

Discussion

28.	The critical speed of a shaft in revolution per second is __________ as that of natural frequency of transverse vibration.
A.	same
B.	different
Answer» B. different

Discussion

29.	Which of the following is a turning pair?
A.	Piston and cylinder of a reciprocating steam engine
B.	Shaft with collars at both ends fitted into a circular hole
C.	Lead screw of a lathe with nut
D.	Ball and a socket joint
Answer» C. Lead screw of a lathe with nut

Discussion

30.	The coriolis component of acceleration is taken into account for
A.	slider crank mechanism
B.	four bar chain mechanism
C.	quick return motion mechanism
D.	all of these
Answer» D. all of these

Discussion

31.	The inertia force is equal to the accelerating force in magnitude, but opposite in direction.
A.	Right
B.	Wrong
Answer» B. Wrong

Discussion

32.	Scott Russell's mechanism is made up of sliding pair.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

33.	Which of the following is an example of a higher pair ?
A.	Toothed gearing
B.	Belt and rope drive
C.	Ball and roller bearing
D.	all of these
Answer» E.

Discussion

34.	Which of the following property of the instantaneous centre is correct ?
A.	A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.
B.	The two rigid links have no linear velocity relative to each other at the instantaneous centre.
C.	The velocity of the instantaneous centre relative to any third rigid link is same whether the instantaneous centre is regarded as a point on the first rigid link or on the second rigid link.
D.	all of the above
Answer» E.

Discussion

35.	The uniform pressure theory gives a higher frictional torque than the uniform wear theory.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

36.	The driving and driven shafts connected by a Hooke's joint will have equal speeds, if
A.	cos θ = sin α
B.	sin θ = ±
C.	tan θ = ±
D.	cot θ = cos α
Answer» D. cot θ = cos α

Discussion

37.	Torsional 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» D. none of these

Discussion

38.	A body is said to vibrate with simple harmonic motion if its acceleration is proportional to the distance from the mean position.
A.	Yes
B.	No
Answer» B. No

Discussion

39.	The virtual or equivalent eccentric for the Meyer's expansion valve is defined as an eccentric having such a length and angle of advance that will cause cut-off to take place at the same position, as is caused by the combined effect of main eccentric and expansion eccentric.
A.	Right
B.	Wrong
Answer» B. Wrong

Discussion

40.	Whitworth quick return motion mechanism is an inversion of a double slider crank chain.
A.	Correct
B.	Incorrect
Answer» C.

Discussion

41.	In a multiple V-belt drive, when a single belt is damaged, it is preferable to change the complete set to
A.	reduce vibration
B.	reduce slip
C.	ensure uniform loading
D.	ensure proper alignment
Answer» D. ensure proper alignment

Discussion

42.	The cam follower generally used in air-craft engines is
A.	knife edge follower
B.	flat faced follower
C.	spherical faced follower
D.	roller follower
Answer» E.

Discussion

43.	If ω/ω is very low for a body vibrating under steady state vibrations, the phase angle for all values of damping factors, will tend to approach
A.	0°
B.	90°
C.	180°
D.	360°
Answer» B. 90°

Discussion

44.	The distance between the centre of suspension and centre of percussion is equal to the equivalent length of a simple pendulum.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

45.	The unbalanced primary forces in a reciprocating engine are
A.	balanced completely
B.	balanced partially
C.	balanced by secondary forces
D.	not balanced
Answer» C. balanced by secondary forces

Discussion

46.	The lower pairs are __________ pairs.
A.	self-closed
B.	force-closed
Answer» B. force-closed

Discussion

47.	The frictional torque transmitted by a disc or plate clutch is same as that of
A.	flat pivot bearing
B.	flat collar bearing
C.	conical pivot bearing
D.	truncated conical pivot bearing
Answer» C. conical pivot bearing

Discussion

48.	A watt's governor can work satisfactorily at speeds from
A.	60 to 80 r.p.m.
B.	80 to 100 r.p.m.
C.	100 to 200 r.p.m.
D.	200 to 300 r.p.m.
Answer» B. 80 to 100 r.p.m.

Discussion

49.	The maximum gyroscopic couple acting on the ship tends to shear the holding down bolts.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

50.	When no external force acts on a body, after giving it an initial displacement, the body is said to have free vibrations.
A.	True
B.	False
Answer» B. False

Discussion

Explore topic-wise MCQs in Mechanical Engineering.

The pitching of a ship produces forces on the bearings which act __________ to the motion of the ship.

At the node, the shaft remains unaffected by the vibration.

When the two elements of a pair have __________ when in motion, it is said to a lower pair.

The tractive force is maximum or minimum when the angle of inclination of crank with the line of stroke (θ) is equal to

A point on a connecting link (excluding end points) of a double slider crank mechanism traces a

The natural frequency of free torsional vibrations of a shaft is equal to (where = Torsional stiffness of the shaft, and = Mass moment of inertia of the disc attached at the end of a shaft)

If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the latter at the same speed will be

A slider moving on a fixed link having constant radius of curvature will have its instantaneous centre at the centre of the circle.

According to Kennedy's theorem, if three bodies move relatively to each other, their instantaneous centres will lie on a

The periodic time is given by (where ω = Angular velocity of the particle in rad/s)

When two links are connected by a pin joint, their instantaneous centre lies

If ω/ω is very high for a body vibrating under steady state vibrations, the phase angle for all values of damping factors, will tend to approach

When the relation between the controlling force () and radius of rotation () for a spring controlled governor is = + , then the governor will be

In vibration isolation system, the transmissibility will be equal to unity, for all values of damping factor, if ω/ω is

If ω/ω = , where co is the frequency of excitation and ω is the natural frequency of vibrations, then the transmissibility of vibration will the

A disturbing mass m1 attached to the rotating shaft may be balanced by a single mass attached in the same plane of rotation as that of , such that (where and are the radii of rotation of and respectively)

When a particle moves round the circumference of a circle of radius with ω rad/s, then its maximum acceleration is ω.

The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (θ) is equal to

The two elements of a pair are said to form a __________ when they permit relative motion between them.

The Whitworth quick return motion mechanism is formed in a slider crank chain when the

The secondary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is

For dynamic balancing of a shaft

When two pulleys are connected by means of an open belt drive, then both the pulleys will rotate is opposite directions.

A mechanism consisting of four links is called a __________ mechanism.

The amplitude of vibration is always __________ the radius of the circle.

In vibration isolation system, if ω/ω > 1, then the phase difference between the transmitted force and the disturbing force is

A very sensitive governor will cause hunting.

The critical speed of a shaft in revolution per second is __________ as that of natural frequency of transverse vibration.

Which of the following is a turning pair?

The coriolis component of acceleration is taken into account for

The inertia force is equal to the accelerating force in magnitude, but opposite in direction.

Scott Russell's mechanism is made up of sliding pair.

Which of the following is an example of a higher pair ?

Which of the following property of the instantaneous centre is correct ?

The uniform pressure theory gives a higher frictional torque than the uniform wear theory.

The driving and driven shafts connected by a Hooke's joint will have equal speeds, if

Torsional vibrations are said to occur when the particles of a body moves

A body is said to vibrate with simple harmonic motion if its acceleration is proportional to the distance from the mean position.

The virtual or equivalent eccentric for the Meyer's expansion valve is defined as an eccentric having such a length and angle of advance that will cause cut-off to take place at the same position, as is caused by the combined effect of main eccentric and expansion eccentric.

Whitworth quick return motion mechanism is an inversion of a double slider crank chain.

In a multiple V-belt drive, when a single belt is damaged, it is preferable to change the complete set to

The cam follower generally used in air-craft engines is

If ω/ω is very low for a body vibrating under steady state vibrations, the phase angle for all values of damping factors, will tend to approach

The distance between the centre of suspension and centre of percussion is equal to the equivalent length of a simple pendulum.

The unbalanced primary forces in a reciprocating engine are

The lower pairs are __________ pairs.

The frictional torque transmitted by a disc or plate clutch is same as that of

A watt's governor can work satisfactorily at speeds from

The maximum gyroscopic couple acting on the ship tends to shear the holding down bolts.

When no external force acts on a body, after giving it an initial displacement, the body is said to have free vibrations.