A watt's governor can work satisfactorily at speeds from
60 to 80 r.p.m.
80 to 100 r.p.m.
100 to 200 r.p.m.
200 to 300 r.p.m.
Correct Answer :
A. 60 to 80 r.p.m.
Related Questions
The Scott-Russell mechanism consists of
Sliding and turning pairs
Sliding and rotary pairs
Turning and rotary pairs
Sliding pairs only
Cylindrical cams can be classified as
Circular
Tangent
Reciprocating
None of the above
Two pulleys of radii r₁ and r₂ and at distance x apart are connected by means of a cross 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
When the crank is at the inner dead centre, in a reciprocating steam engine, then the acceleration of the piston will be
ω²r. (n + 1)/n
ω²r. (n - 1)/n
ω²r. n/(n + 1)
ω²r. n/(n - 1)
In a vibrating system, if the actual damping coefficient is 40 N/m/s and critical damping coefficient is 420 N/m/s, then logarithmic decrement is equal to
0.2
0.4
0.6
0.8
The equation of motion for a vibrating system with viscous damping is (d²x/dt²) + (c/m). (dx/dt) + (s/m). x = 0 If the roots of this equation are real, then the system will be
Over-damped
Under damped
Critically damped
Without vibrations
The balancing of a rigid rotor can be achieved by appropriately placing balancing masses in
A single plane
Two planes
Three planes
Four planes
In a four stroke I.C. engine, the turning moment during the compression stroke is
Positive throughout
Negative throughout
Positive during major portion of the stroke
Negative during major portion of the stroke
A slider crank chain consists of following numbers of turning and sliding pairs
1, 3
2, 2
3, 1
4, 0
A circular bar moving in a round hole is an example of
Incompletely constrained motion
Partially constrained motion
Completely constrained motion
Successfully constrained motion
The acceleration of a particle at any instant has two components i.e. radial component and tangential component. These two components will be
Parallel to each other
Perpendicular to each other
Inclined at 45°
Opposite to each other
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
In locomotives, the ratio of the connecting rod length to me crank radius is kept very large in order to
Minimise the effect of primary forces
Minimise the effect of secondary forces
Have perfect balancing
To start the locomotive quickly
For two governors A and B, the lift of sleeve of governor A is more than that of governor B, for a given fractional change in speed. It indicates that
Governor A is more sensitive than governor B
Governor B is more sensitive than governor A
Both governors A and B are equally sensitive
None of the above
The Coriolis component of acceleration acts
Along the sliding surface
Perpendicular to the sliding surface
At 45° to the sliding surface
Parallel to the sliding surface
The critical speed of a shaft depends upon its
Mass
Stiffness
Mass and stiffness
Stiffness and eccentricity
With single Hooke's joint it is possible to connect two shafts, the axes of which have an angular misalignment up to
10°
20°
30°
40°
Two heavy rotating masses are connected by shafts of lengths l₁, l₂ and l₃ and the corresponding diameters are d₁, d₂ and d₃. This system is reduced to a torsionally equivalent system having uniform diameter d = d₁ of the shaft. The equivalent length of the shaft is
(l₁ + l₂ + l₃)/3
l = l₁ + l₂.(d₁/d₂)³ + l₂.(d₁/d₃)³
l = l₁ + l₂.(d₁/d₂)⁴ + l₃.(d₁/d₃)⁴
l₁ + l₂ + l₃
In a mechanism, the fixed instantaneous centres are those centres which
Remain in the same place for all configurations of the mechanism
Vary with the configuration of the mechanism
Moves as the mechanism moves, but joints are of permanent nature
None of the above
Which of the following is an inversion of Single slider crank chain?
Beam engine
Rotary engine
Oldhams coupling
Elliptical trammel
The frequency of oscillation of a compound pendulum is
2π. √[gh/(kG² + h²)]
2π. √[(kG² + h²)/gh]
(1/2π). √[gh/(kG² + h²)]
(1/2π). √[(kG² + h²)/gh]
The main disadvantage of the sliding pair is that it is
Bulky
Wears rapidly
Difficult to manufacture
Both (A) and (B) above
The two elements of a pair are said to form a _________ when they permit relative motion between them.
Open pair
Kinematic pair
Sliding pair
None of these
The product of the diametral pitch and circular pitch is equal to
1
1/π
π
2 π
Sense of tangential acceleration of a link
Is same as that of velocity
Is opposite to that of velocity
Could be either same or opposite to velocity
Is perpendicular to that of velocity
The Bifilar suspension method is used to determine
Natural frequency of vibration
Position of balancing weights
Moment of inertia
Centripetal acceleration
Longitudinal vibrations are said to occur when the particles of a body moves
Perpendicular to its axis
Parallel to its axis
In a circle about its axis
None of these
The example of completely constrained motion is a
Motion of a piston in the cylinder of a steam engine
Motion of a square bar in a square hole
Motion of a shaft with collars at each end in a circular hole
All of the above
The contact ratio is the ratio of
Length of pair of contact to the circular pitch
Length of arc of contact to the circular pitch
Length of arc of approach to the circular pitch
Length of arc of recess to the circular pitch
Power of a governor is the
Mean force exerted at the sleeve for a given percentage change of speed
Workdone at the sleeve for maximum equilibrium speed
Mean force exerted at the sleeve for maximum equilibrium speed
None of the above