The acceleration of the particle moving with simple harmonic motion is _________ at the mean position.
Zero
Minimum
Maximum
None of these
Correct Answer :
A. Zero
Related Questions
In a simple train of wheels, the velocity ratio __________ the intermediate wheels.
Depends upon
Is independent of
Either A or B
None of these
The mechanism consisting of three turning pairs and one sliding pair, is called a
Single slider crank chain
Whitworth quick return motion mechanism
Crank and slotted lever quick return motion mechanism
All of the above
Which one of the following can completely balance several masses revolving in different planes on a shaft?
A single mass in different planes
Two masses in any two planes
A single mass in one of the planes of the revolving masses
Two equal masses in any two planes
One end of a helical spring is fixed while the other end carries the load W which moves with simple harmonic motion. The frequency of motion is given by (where δ = Deflection of the spring)
2π. √(g/δ)
1/2π. √(g/δ)
2π. √(δ/g)
1/2π. √(δ/g)
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
The instantaneous centres which vary with the configuration of mechanism are called
Permanent instantaneous centres
Fixed instantaneous centres
Neither fixed nor permanent instantaneous centres
None of the above
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
In a four bar chain or quadric cycle 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 Klein's method of construction for reciprocating engine mechanism
Is based on acceleration diagram
Is a simplified form of instantaneous center method
Utilises a quadrilateral similar to the diagram of mechanism for reciprocating engine
Enables determination of Carioles component
The ratio of the driving tensions for V-belts is __________ times that of flat belts. (Where β = Semi-angle of the groove)
sinβ
cosβ
cosecβ
secβ
If the controlling force line for a spring controlled governor when produced intersects the Y-axis at the origin, then the governor is said to be
Stable
Unstable
Isochronous
None of these
An imaginary circle which by pure rolling action, gives the same motion as the actual gear, is called
Addendum circle
Dedendum circle
Pitch circle
Clearance circle
A completely constrained motion can be transmitted with.
1 link with pin joints
2 links with pin joints
3 links with pin joints
4 links with pin joints
If some links are connected such that motion between them can take place in more than one direction, it is called
Incompletely constrained motion
Partially constrained motion
Completely constrained motion
Successfully constrained motion
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
The contact ratio for gears is
Zero
Less than one
Greater than one
Infinity
The example of successfully constrained motion is a
Motion of an I.C. engine valve
Motion of the shaft between a footstep bearing
Piston reciprocating inside an engine cylinder
All of the above
The frictional torque transmitted by a disc or plate clutch is same as that of
Flat pivot bearing
Flat collar bearing
Conical pivot bearing
Truncated conical pivot bearing
A system in dynamic balance implies that
The system is critically damped
There is no critical speed in the system
The system is also statically balanced
There will absolutely no wear of bearings
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°
When a shaking force is transmitted through the springs, damping becomes detrimental when the ratio of its frequency to the natural frequency is greater than
0.25
0.5
1
2
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
The velocity of a particle moving with simple harmonic motion, at any instant is given by (where ω = Displacement of the particle from mean position)
ω √(x² - r²)
ω √(r² - x²)
ω² √(x² - r²)
ω² √(r² - x²)
Cam size depends upon
Base circle
Pitch circle
Prime circle
Outer circle
A mechanism is an assemblage of
Two links
Three links
Four or more than four links
All of these
A point B on a rigid link AB moves with respect to A with angular velocity ω rad/s. The radial component of the acceleration of B with respect to A, is (where vBA = Linear velocity of B with respect to A)
vBA × AB
vBA /AB
v²BA
v²BA /AB
The type of coupling used to join two shafts whose axes are neither in same straight line nor parallel, but intersect is
Flexible coupling
Universal coupling
Chain coupling
Oldham's coupling
The method of obtaining different mechanisms by fixing in turn different links in a kinematic chain, is known as
Structure
Machine
Inversion
Compound mechanism
In gears, interference takes place when
The tip of a tooth of a mating gear digs into the portion between base and root circles
Gears do not move smoothly in the absence of lubrication
Pitch of the gears is not same
Gear teeth are undercut
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