The velocity of piston in a reciprocating steam engine is given by (where ω = Angular velocity of crank, r = Radius of crank pin circle, θ = Angle turned by crank from inner dead centre, and n = Ratio of length of connecting rod to the radius of crank)
ωr [sin θ + (sin 2θ/n)]
ωr [cos θ + (cos 2θ/n)]
ω²r [sin θ + (sin 2θ/n)]
ω²r [cos θ + (cos 2θ/n)]
Correct Answer :
A. ωr [sin θ + (sin 2θ/n)]
Related Questions
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)
The maximum frictional force, which comes into play, when a body just begins to slide over the surface of the other body, is known as
Static friction
Dynamic friction
Limiting friction
Coefficient of friction
A point on a link connecting double slider crank chain traces a
Ellipse
Circle
Parabola
Hyperbola
The coriolis component of acceleration exists whenever a point moves along a path that has
Linear displacement
Rotational motion
Gravitational acceleration
Tangential acceleration
For an involute gear, the ratio of base circle radius and pitch circle radius is equal to
sinφ
cosφ
secφ
cosecφ
The periodic time of one oscillation for a simple pendulum is
2π. √(g/l)
(1/2π). √(g/l)
2π. √(l/g)
(1/2π). √(l/g)
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
In order to double the period of a simple pendulum, the length of the string should be
Halved
Doubled
Quadrupled
None of these
When there is a reduction in amplitude over every cycle of vibration, then the body is said to have
Free vibration
Forced vibration
Damped vibration
Under damped vibration
The example of higher pair is
Belt, rope and chain drives
Gears, cams
Ball and roller bearings
All of the above
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
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 total number of instantaneous centres for a mechanism consisting of n links are
n/2
n
n - 1
n(n - 1)/2
Governor is used in automobile to
Decrease the variation of speed
Maximize the fuel economy
Limit the vehicle speed
Maintain constant engine speed
In vibration isolation system, the transmissibility will be equal to unity, for all values of damping factor, if ω/ωn is
Equal to 1
Equal to 2
Less than 2
Greater than 2
In higher pair, the relative motion is
Purely turning
Purely sliding
Purely rotary
Combination of sliding and turning
The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because, the
Unbalanced couples are caused only at higher speeds
Unbalanced forces are not dangerous at higher speeds
Effects of unbalances are proportional to the square of the speed
Effects of unbalances are directly proportional to the speed
The velocity of the belt for maximum power is (where m = Mass of the belt in kg per metre length)
T/3
(T.g)/3
√(T/3m)
√(3m/T)
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 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
In a simple harmonic motion, the velocity vector with respect to displacement vector
Is in phase
Leads by 90°
Leads by 180°
Lags by 90°
The static friction
Bears a constant ratio to the normal reaction between the two surfaces
Is independent of the area of contact, between the two surfaces
Always acts in a direction, opposite to that in which the body tends to move
All of the 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
In a radial cam, the follower moves
In a direction perpendicular to the cam axis
In a direction parallel to the cam axis
In any direction irrespective of the cam axis
Along the cam axis
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
When a body moves with simple harmonic motion, the product of its periodic time and frequency is equal to
Zero
One
π/2
π
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
Four times the first one
Same as the first one
One fourth of the first one
One and a half times the first one
In a differential band brake as shown in the below figure, if the length OB is greater than OA, then the force P at C should act in the downward direction. 
Yes
No
Unpredictable
None of these
In a simple train of wheels, the velocity ratio __________ the intermediate wheels.
Depends upon
Is independent of
Either A or B
None of these
Which of the following is a lower pair?
Ball and socket i
Piston and cylinder
Cam and follower
Both (A) and (B) above