The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (θ) is equal to
90° and 180°
45° and 225°
180° and 270°
270° and 360°
Correct Answer :
B. 45° and 225°
Related Questions
For fluctuating loads, well suited bearing is
Ball bearing
Roller bearing
Needle roller bearing
Thrust bearing
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)
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 method of obtaining different mechanisms by fixing in turn different links in a kinematic chain, is known as
Structure
Machine
Inversion
Compound mechanism
Flexible coupling is used because
It is easy to disassemble
It is easy to engage and disengage
It transmits shocks gradually
It prevents shock transmission and eliminates stress reversals
Rectangular bar in a rectangular hole is the following type of pair
Completely constrained motion
Partially constrained motion
Incompletely constrained motion
Freely constrained motion
When the two elements of a pair have a surface contact when relative motion takes place and the surface of one element slides over the surface of the other, the pair formed is known as a
Lower pair
Higher pair
Self-closed pair
Force-closed pair
The inversion of a mechanism is
Changing of a higher pair to a lower pair
Turning its upside down
Obtained by fixing different links in a kinematic chain
Obtained by reversing the input and output motion
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
Effort 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
Which of the following is an inversion of Single slider crank chain?
Beam engine
Rotary engine
Oldhams coupling
Elliptical trammel
The velocity of sliding __________ the distance of the point of contact from the pitch point.
Is directly proportional to
Is inversely proportional to
Is equal to cos φ multiplied by
Does not depend upon
The size of a gear is usually specified by
Pressure angle
Circular pitch
Diametral pitch
Pitch circle diameter
When the sleeve of a Porter governor moves upwards, the governor speed
Increases
Decreases
Remain unaffected
First increases and then decreases
A cam with a roller follower would constitute following type of pair
Lower pair
Higher pair
Open pair
Close pair
It is required to connect two parallel shafts, the distance between whose axes is small and variable. The shafts are coupled by
Universal joint
Knuckle joint
Oldham's coupling
Flexible coupling
Which of the following statement is wrong?
The difference between the maximum and minimum energies is called maximum fluctuation of energy
The coefficient of fluctuation of speed is the ratio of maximum fluctuation of speed to the mean speed
The variations of energy above and below the mean resisting torque line is known as fluctuation of energy
None of the above
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
If the pressure angle is __________, a reciprocating follower will jam in its bearings.
Small
Too small
Large
Too large
The frictional torque transmitted in a flat pivot bearing, assuming uniform wear, is (Where μ = Coefficient of friction, W=Load over the bearing, R=Radius of bearing)
μwr
¾μWR
(2/3) μWR
½μWR
Which of the following statement is correct?
The power absorbed in operating the piston valve is less than D-slide valve
The wear of the piston valve is less than the wear of the D-slide valve
The D-slide valve is also called outside admission valve.
All of the above
The frictional torque transmitted by a cone clutch is same as that of
Flat pivot bearing
Flat collar bearing
Conical pivot bearing
Truncated conical pivot bearing
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
4
3
None of the above
The power transmitted by a belt is maximum when the maximum tension in the belt is _________ of centrifugal tension.
One-third
Two-third
Double
Three times
When a ship travels in a sea, which of the effect is more dangerous
Steering
Pitching
Rolling
All of the above
The frictional torque transmitted in a truncated conical pivot bearing, considering uniform wear, is
(1/2). μ W cosec α (r₁ + r₂)
(2/3).μ W cosec α (r₁ + r₂)
(1/2). μ W cosec α [(r₁³ - r₂³)/(r₁² - r₂²)]
(2/3). μ W cosec α [(r₁³ - r₂³)/(r₁² - r₂²)]
A slider moves at a velocity v on a link revolving at ω rad/s. The coriolis component of acceleration is
ωv
2ωv
ω²v
2ωv²
In a single slider crank chain
Each of the four pairs is a turning pair
One is a turning pair and three are sliding pairs
Two are turning pairs and two are sliding pairs
Three are turning pairs and one is a sliding pair
The magnitude of velocities of the points on a rigid link is
Directly proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre
Directly proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre
Inversely proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre
Inversely proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre
The secondary unbalanced force is __________ the primary unbalanced force.
One-half
Two-third
n times
1/n times