When one of the links of a kinematic chain is fixed, the chain is known as a
Structure
Mechanism
Inversion
Machine
Correct Answer :
B. Mechanism
Related Questions
Shaft revolving in a bearing is the following type of pair
Lower pair
Higher pair
Spherical pair
Cylindrical pair
In a rigid link OA, velocity of A w.r.t. O will be
Parallel to OA
Perpendicular to OA
At 45° to OA
Along AO
The approximate straight line mechanism is a
Four bar linkage
6 bar linkage
8 bar linkage
3 bar linkage
A pantograph is a mechanism with
Lower pairs
Higher pairs
Rolling pairs
Turning pairs
The maximum efficiency of spiral gears is (where θ = Shaft angle, and φ = Friction angle)
sin (θ + φ) + 1/ cos (θ - φ) + 1
cos (θ - φ) + 1/ sin (θ + φ) + 1
cos (θ + φ) + 1/ cos (θ - φ) + 1
cos (θ - φ) + 1/ cos (θ + φ) + 1
Instantaneous center of rotation of a link in a four bar mechanism lies on
Right side pivot of this link
Left side pivot of this link
A point obtained by intersection on extending adjoining links
Cant occur
The centre of percussion is below the centre of gravity of the body and is at a distance equal to
h/kG
h²/kG
kG²/h
h × kG
Crowning on pulleys helps
In increasing velocity ratio
In decreasing the slip of the belt
For automatic adjustment of belt position so that belt runs centrally
Increase belt and pulley life
In a coupling rod of a locomotive, each of the four pairs is a ________ pair.
Sliding
Turning
Rolling
Screw
Which gear is used for connecting two coplanar and intersecting shafts?
Spur gear
Helical gear
Bevel gear
None of the above
Coriolis component acts
Perpendicular to sliding surfaces
Along sliding surfaces
Somewhere in between above two
None of the above
The length of a simple pendulum which gives the same frequency as the compound pendulum, is
kG + l₁
kG² + l₁
(kG² + l₁²)/ l₁
(kG + l₁²)/ l₁
Two pulleys of radii r₁ and r₂ and at distance x apart are connected by means of an open belt drive. The length of the belt is
π (r₁ + r₂) + (r₁ + r₂)²/x + 2x
π (r₁ + r₂) + (r₁ - r₂)²/x + 2x
π (r₁ - r₂) + (r₁ - r₂)²/x + 2x
π (r₁ - r₂) + (r₁ + r₂)²/x + 2x
In S.H.M., acceleration is proportional to
Velocity
Displacement
Rate of change of velocity
All of the above
The frictional torque transmitted in a conical pivot bearing, considering uniform pressure, is (where R = Radius of shaft, and α = Semi-angle of the cone)
(1/2) μ W R cosecα
(2/3) μ W R cosecα
(3/4) μ W R cosecα
μ W R cosecα
A body in motion will be subjected to coriolis acceleration when that body is
In plane rotation with variable velocity
In plane translation with variable velocity
In plane motion which is a resultant of plane translation and rotation
Restrained to rotate while sliding over another body
The primary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is
0° and 90°
0° and 180°
90° and 180°
180° and 360°
The number of links and instantaneous centers in a reciprocating engine mechanism are
4, 4
4, 5
5, 4
4, 6
Which of the following is an inversion of a double slider crank chain?
Oldham's coupling
Elliptical trammel
Scotch yoke mechanism
All of these
The gear train usually employed in clocks is a
Simple gear train
Reverted gear train
Sun and planet gear
Differential gear
In order to balance the reciprocating masses,
Primary forces and couples must be balanced
Secondary forces and couples must be balanced
Both (A) and (B)
None of these
The arrangement is called bevel gearing, when two __________ are connected by gears.
Intersecting and coplanar shafts
Nonintersecting and non-coplanar shafts
Parallel and coplanar shafts
Parallel and non-coplanar shafts
A disc is a spinning with an angular velocity ω 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 ωP = Angular velocity of precession of the axis of spin)
(1/2).Iω²
Iω²
(1/2). I ω ωP
I ω ωP
The contact ratio for gears is
Zero
Less than one
Greater than one
Infinity
A governor is said to be stable, if the
Radius of rotation of balls increases as the equilibrium speed decreases
Radius of rotation of balls decreases as the equilibrium speed decreases
Radius of rotation of balls increases as the equilibrium speed increases
Radius of rotation of balls decreases as the equilibrium speed increases
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
5,367 r.p.m.
6,000 r.p.m.
9,360 r.p.m.
12,000 r.p.m.
The direction of linear velocity of any point on a link with respect to another point on the same link is
Parallel to the link joining the points
Perpendicular to the link joining the points
At 45° to the link joining the points
None of the above
A universal joint is an example of
Higher pair
Lower pair
Rolling pair
Sliding pair
In a turning moment diagram, the variations of energy above and below the mean resisting torque line is called
Fluctuation of energy
Maximum fluctuation of energy
Coefficient of fluctuation of energy
None of these
A simple spring-mass vibrating system has a natural frequency of fn. If the spring stiffness is halved and the mass is doubled, then the natural frequency will become
fn/2
2 fn
4 fn
8 fn