List of Objective Questions On Theory Of Machines Part – 2
1.In a darg link quick return mechanism, the shortest link is always fixed. The sum of the shortest and longest link is
equal to sum of other two
greater than sum of other two
less than sum of other two
there is no such relationship
none of the above.
ANSWER : : less than sum of other two
2.Whitworth quick return mechanism is obtained by inversion of
slider crank mechanism
kinematic chain
five link mechanism
roller cam mechanism
none of the above.
ANSWER : : slider crank mechanism
3.The main disadvantage of the sliding pair is that it is
bulky
wears rapidly
difficult to manufacture
(a) and (b) above
(a) and (c) above.
ANSWER : : (a) and (b) above
4.If the opposite links of a four bar linkage are equal, the links will always form a
triangle
rectangle
parallelogram
pentagon
trapezoid.
ANSWER : : parallelogram
5.Hart mechanism has
eight links
six links
four links
twelve links
five links.
ANSWER : : six links
6.Higher pairs are those which have
point or line contact between the two elements when in motion
surface contact between the two elements when in motion
elements of pairs not held together mechanically
two elements that permit relative motion
none of the above.
ANSWER : : point or line contact between the two elements when in motion
7.Kinematic pairs are those which have
point or line contact between the two elements when in motion
surface contact between the two elements when in motion
elements of pairs not held together mechanically
two elements that permit relative motion
none of the above.
ANSWER : : two elements that permit relative motion
8.A point on a link connecting double slider crank chain traces a
straight line
circle
parabola
hyperbola
ellipse.
ANSWER : : ellipse.
9.A cam mechanism imparts following motion
rotating
oscillating
reciprocating
all of the above
none of the above.
ANSWER : : all of the above
10.Peaucellier mechanism has
eight links
six links
four links
twelve links
five links.
ANSWER : : eight links
11.Open pairs are those which have
point or line contact between the two elements when in motion
surface contact between the two elements when in motion
elements of pairs not held together mechanically
two elements that permit relative motion
none of the above.
ANSWER : : elements of pairs not held together mechanically
12.A pantograph is a mechanism with
lower pairs
higher pairs
rolling pairs
turning pairs
spherical pairs.
ANSWER : : lower pairs
13.A chain comprises of 5 links having 5 joints. Is it kinematic chain ?
yes
no
it is a marginal case
data are insufficient to determine it
unpredictable.
ANSWER : : no
14.Which of the following mechanisms produces mathematically an exact straight line motion
Grasshopper mechanism
Watt mechanism
Peaucellier’s mechanism
Tchabichiff mechanism
Ackermann mechanism.
ANSWER : : Peaucellier’s mechanism
15.For a kinematic chain to be considered as mechanism
two links should be fixed
one link should be fixed
none of the links should be fixed
there is no such criterion
none of the above.
ANSWER : : one link should be fixed
16.The approximate straight line mechanism is a
four bar linkage
6 bar linkage
8 bar linkage
3 bar linkage
5 bar linkage.
ANSWER : : four bar linkage
17.The following is the inversion of slider crank chain mechanism
Whit worth quick return mechanism
hand pump
oscillating cylinder engine
all of the above
none of the above.
ANSWER : : all of the above
18.In a mechanism, usually one link is fixed. If the fixed link is changed in a kinematic chain, then relative motion of other links
will remain same
will change
could change or remain unaltered depending oh which link is fixed
will not occur
none of the above.
ANSWER : : will remain same
19.A kinematic chain requires at least
2 links and 3 turning pairs
3 links and 4 turning pairs
4 links and 4 turning pairs
5 links and 4 turning pairs
none of the above.
ANSWER : : 4 links and 4 turning pairs
20.Kinematic pairs are those which have
two elements held together mechanically
two elements having relative motion
two elements having Coroili’s component
minimum of two instantaneous centers
all of the above.
ANSWER : : two elements having relative motion
21.A cam with a roller follower would con statute following type of pair
lower pair
higher pair
open pair
close pair
cam pair.
ANSWER : : higher pair
22.In its simplest form, a cam mechanism consists of following number of links
1
2
3
4
none.
ANSWER : : 3
23.An eccentric sheave pivoted at one point rotates and transmits oscillatory motion to a link whose one end is pivoted and other end is connected to it. This mechanism has
2 links
3 links
4 links
5 links
none of the above.
ANSWER : : 4 links
24.According to Kennedy’s theorem, if three bodies have plane motions, their instantaneous centers lie on
a triangle
a point
two lines
a straight line
a curve.
ANSWER : : a straight line
25.The frequency of oscillation at compared to earth will be
6 times more
6 times less
2.44 times more
2.44 times,less
36 times less.
ANSWER : : 2.44 times,less
26.The absolute acceleration of any point P in a link about center of rotation 0 is
along PO
perpendicular to PO
at 45� to PO
along OP
none of the above.
ANSWER : : none of the above.
27.For simple harmonic motion of the of follower, a cosine curve represents
displacement diagram
velocity diagram
acceleration diagram
all of the above
none of the above.
ANSWER : : acceleration diagram
28.If the radius of gyration of a compound pendulum about an axis through e.g. is more, then its frequency of oscillation will be
less
more
same
data are insufficient to determine same
none of the above.
ANSWER : : less
29.The number of links and instantaneous centers in a reciprocating engine mechanism are
4, 4
4, 5
5, 4
6, 4
4, 6.
ANSWER : : 4, 6.
30.The Bifilar suspension method is used to determine
natural frequency of vibration
position of balancing weights
moment of inertia
centripetal acceleration’
angular acceleration of a body.
ANSWER : : moment of inertia
31.Angular acceleration of a link can be determined by dividing the
centripetal component of acceleration with length of link
tangential component of acceleration with length of link
resultant acceleration with length of link
all of the above
none of the above.
ANSWER : : tangential component of acceleration with length of link
32.The velocity of any point in mechanism relative to any other point on the mechanism on velocity polygon is represented by the line
joining the corresponding points
perpendicular to line as per (a)
not possible to determine with these data
at 45� to line as per (a)
none of the above.
ANSWER : : joining the corresponding points
33.In above example, the minimum length of the coupler will be
45 mm
slightly less than 45 mm
slightly more than 45 mm
95 mm
none of the above.
ANSWER : : slightly more than 45 mm
34.In a shape mechanism, the Corioli’s component of acceleration will
not exist
exist
depend on position of crank
unpredictable
none of the above.
ANSWER : : exist
35.Which is the false statement about the properties of instantaneous center
at the instantaneous center of rotation, one rigid link rotates instantaneously relative to another for the configuration of mechanism considered
the two rigid links have no linear velocities relative to each other at the instantaneous center
the two rigid links which have no linear velocity relative to each other at this center have the same linear velocity to the third rigid link
the double center can be denoted either by 02\ or Ol2, but proper selection should be made
none of the above.
ANSWER : : the double center can be denoted either by 02\ or Ol2, but proper selection should be made
36.The magnitude of tangential acceleration is equal to
velocity2 x crank radius
velocity vcrankradius
(velocity/crankradius)
velocity x crank radius2
none of the above.
ANSWER : : velocity vcrankradius
37.In a rigid link OA, velocity of A w.r.t. will be
parallel to OA
perpendicular to OA
at 45� to OA
along AO
along OA.
ANSWER : : perpendicular to OA
38.The direction of Corioli’s component of acceleration is the direction
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
along the centripetal acceleration
along tangential acceleration
along perpendicular to angular velocity
none of the above.
ANSWER : : 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
39.Inertia force acts
perpendicular to the accelerate force
along the direction of accelerate force
opposite to the direction of accelerate force
in any direction w.r.t. accelerate force depending on the magnet two
none of the above.
ANSWER : : opposite to the direction of accelerate force
40.Tangential acceleration direction is
along the angular velocity
opposite to angular velocity
may be any one of these
perpendicular to angular velocity
none of the above.
ANSWER : : may be any one of these
41.Two systems shall be dynamically equivalent when
the mass of two are same
e.g. of two coincides
M.I. of two about an axis through e.g. is equal
all of the above
none of the above.
ANSWER : : all of the above
42.Instantaneous center of rotation of a link in a four bar mechanism lies on
right side pivot of this link
lift side pivot of this link
a point obtained by intersection on extending adjoining links
can’t occur
none of the above.
ANSWER : : a point obtained by intersection on extending adjoining links
43.The maximum value of the pressure angle in case of cam is kept as
10�
14�
20�
30�
25�.
ANSWER : : 30�
44.Angle of dwell of cam is defined as the angle
during which the follower returns to its initial position
of rotation of the cam for definite displacement of the follower
through which the cam rotates during the period in which the follower remains in the highest position
moved by the cam from the instant the follower begins to rise, till it reaches its highest position
moved by the cam from a beginning of ascent to the termination of descent.
ANSWER : : through which the cam rotates during the period in which the follower remains in the highest position
45.The pressure angle of a cam depends upon
offset between center lines of cam and follower
lift of follower
angle of ascent
sum of radii of base circle and roller follower
all of the above.
ANSWER : : all of the above.
46.Corioli’s component acts
perpendicular to sliding surfaces
along sliding surfaces
somewhere in between above two
unpredictable
none of the above.
ANSWER : : perpendicular to sliding surfaces
47.Cylindrical cams can be classified as
circular
tangent
reciprocating
all of the above
none of the above.
ANSWER : : none of the above.
48.Klein’s construction can be used when
crank has a uniform angular velocity
crank has non-uniform velocity
crank has uniform angular acceleration
crank has uniform angular velocity and angular acceleration
there is no such criterion.
ANSWER : : crank has a uniform angular velocity
49.For the same lift and same angle of ascent, a smaller base circle will give
a small value of pressure angle
a large value of pressure angle
there is no such relation with pressure angle
something else
none of the above is true.
ANSWER : : a large value of pressure angle
50.The number of load centers in a crank driven slider crank mechanism are
0
2
4
6
may be any number depending upon position of mechanism.
ANSWER : : 2
51.The sense of Corioli’s component is such that it
leads the sliding velocity vector by 90�
lags the sliding velocity vector by 90�
is along the sliding velocity vector
leads the sliding velocity vector by 180�
none of the above.
ANSWER : : leads the sliding velocity vector by 90�
52.Klein’s construction is useful to determine
velocity of various parts
acceleration of various parts
displacement of various parts
angular acceleration of various parts
all of the above.
ANSWER : s: b
53.Klein’s construction gives a graphics construction for
slider-crank mechanism
velocity polygon
acceleration polygon
four bar chain mechanism
angular acceleration.
ANSWER : : acceleration polygon
54.A circle passing through the pitch point with its center at the center of cam axis is known as
pitch circle
base circle
prime circle
outer circle
cam circle.
ANSWER : : prime circle
55.Angle of action of cam is defined as the angle
during which the follower returns to its initial position
of rotation of the cam for a definite displacement of the follower
through which the cam rotates during the period in which the follower remains in the highest position
moved by the cam from the instant the follower begins to rise, till it reaches its highest position
moved by the cam from beginning of ascent to the termination of descent.
ANSWER : : moved by the cam from beginning of ascent to the termination of descent.
56.Cam size depends upon
base circle
pitch circle
prime circle
outer circle
none of the above.
ANSWER : : base circle
57.Angle of descent of cam is defined as the angle
during which the follower returns to its initial position
of rotation of the cam for a definite displacement of the follower
through which the cam rotates during the period in which the follower remains in the highest position
moved by the cam from the instant the follower begins to rise, till it reaches its highest position
moved by the cam from beginning of ascent to the termination of descent.
ANSWER : : during which the follower returns to its initial position
58.Cam angle is defined as the angle
during which the follower returns to its initial position
of rotation of the cam for a definite displacement of the follower
through which, the cam rotates during the period in which the follower remains in the highest position
moved by the cam from the instant the follower begins to rise, till it reaches its highest position
moved by the cam from beginning of i ascent to the termination of descent.
ANSWER : : of rotation of the cam for a definite displacement of the follower
59.Klein’s construction can be used to determine acceleration of various parts when the crank is at
inner dead center
outer dead center
right angles to the link of the stroke
at 45� to the line of the stroke
all of the above.
ANSWER : : all of the above.