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
Correct Answer :
C. Radius of rotation of balls increases as the equilibrium speed increases
Related Questions
In steady state forced vibrations, the amplitude of vibrations at resonance is __________ damping coefficient.
Equal to
Directly proportional to
Inversely proportional to
Independent of
A disturbing mass m₁ attached to the rotating shaft may be balanced by a single mass m₂ attached in the same plane of rotation as that of m₁, such that (where r₁ and r₂ are the radii of rotation of m₁ and m₂ respectively)
m₁r₂ = m₂r₁
m₁r₁ = m₂r₂
m₁m₂ = r₁r₂
None of these
The acceleration of a particle moving with simple harmonic motion, at any instant is given by
ωx
ω²x
ω²/x
ω³/x
Which of the following is an example of sliding pair?
Piston and cylinder of a reciprocating steam engine
Shaft with collars at both ends fitted into a circular hole
Lead screw of a lathe with nut
Ball and a socket joint
A mass of 1 kg is attached to the end of a spring with a stiffness of 0.7 N/mm. The critical damping coefficient of this system is
1.4 N-s/m
18.52 N-s/m
52.92 N-s/m
529.2 N-s/m
Which of the following statements regarding laws governing the friction between dry surfaces are correct?
The friction force is dependent on the materials of the contact surfaces.
The friction force is directly proportional to the normal force.
The friction force is independent of me area of contact.
All of the above
Coriolis component acts
Perpendicular to sliding surfaces
Along sliding surfaces
Somewhere in between above two
None of the above
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.
All of the above
In order to double the period of a simple pendulum, the length of the string should be
Halved
Doubled
Quadrupled
None of these
The effort of a Porter governor is equal to (where c = Percentage increase in speed, m = Mass of ball, and M = Mass on the sleeve)
c (m - M) g
c (m + M) g
c/(m + M) g
c/(m - M) g
Peaucelliers mechanism has
Eight links
Six links
Four links
Twelve links
Kinematic pairs are those which have two elements that
Have line contact
Have surface contact
Permit relative motion
Are held together
The angle of inclination of the plane, at which the body begins to move down the plane is called
Angle of friction
Angle of repose
Angle of projection
None of these
The height of a Watt's governor (in metres) is equal to (where N = Speed of the arm and ball about the spindle axis)
8.95/N²
89.5/N²
895/N²
8950/N²
The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as
Damping factor
Damping coefficient
Logarithmic decrement
Magnification factor
The maximum or minimum value of the swaying couple is
± c.m.ω².r
± a (1 - c) m.ω².r
± (a/√2) (1 - c) m.ω².r
± 2a (1 - c) m.ω².r
The primary unbalanced force due to inertia of reciprocating parts in a reciprocating engine is given by (where m = Mass of reciprocating parts, ω = Angular speed of crank, r = Radius of crank, θ = Angle of inclination of crank with the line of stroke, and n = Ratio of the length of connecting rod to radius of crank)
m.ω².r sinθ
m.ω².r cosθ
m.ω².r (sin 2θ/n)
m.ω².r (cos 2θ/n)
Which of the following disciplines provides study of relative motion between the parts of a machine?
Theory of machines
Applied mechanics
Mechanisms
Kinematics
Which of the following is a lower pair?
Ball and socket i
Piston and cylinder
Cam and follower
Both (A) and (B) above
A Hartnell governor has its controlling force (Fc) given by Fc = ar + b, where r is the radius of rotation and a and b are constants. The governor becomes isochronous when
a is +ve and b = 0
a = 0 and b is +ve
a is +ve and b is -ve
a is +ve and b is also +ve
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
The natural frequency of free transverse vibrations due to a point load acting over a simply supported shaft is equal to (where δ = Static deflection of a simply supported shaft due to the point load)
0.4985/√δ
0.5615/√δ
0.571/√δ
0.6253/√δ
The coriolis component of acceleration depends upon
Velocity of slider
Angular velocity of the link
Both (A) and (B)
None of these
The magnitude of linear velocity of a point B on a link AB relative to point A is (Where ω = Angular velocity of the link AB)
ω × AB
ω × (AB)²
ω² × AB
(ω × AB)²
Cylindrical cams can be classified as
Circular
Tangent
Reciprocating
None of the above
The locus of a point on a thread unwound from a cylinder will be
A straight line
A circle
Involute
Cycloidal
The type of gears used to connect two non parallel and non intersecting shafts is
Spur gear
Helical gear
Bevel gear
Spiral gear
The Klein's method of construction for reciprocating engine mechanism
Is a simplified version of instantaneous centre method
Utilises a quadrilateral similar to the diagram of mechanism for reciprocating engine
Enables determination of coriolis component
Is based on the acceleration diagram
In its simplest form, a cam mechanism consists of following number of links
1
2
3
4
A fixed gear having 200 teeth is in mesh with another gear having 50 teeth. The two gears are connected by an arm. The number of turns made by the smaller gear for one revolution of arm about the centre of bigger gear is
2
3
4
5