In vibration isolation system, if ω/ωn < 2, then for all values of damping factor, the transmissibility will be (where ω = Angular speed of the system, ωn = Natural frequency of vibration of the system)
Less than unity
Equal to unity
Greater than unity
Zero
Correct Answer :
C. Greater than unity
Related Questions
A rotor which is balanced statically but not dynamically is supported on two bearings L apart and at high speed of the rotor, reaction on the left bearing is R. The right side of the bearing is shifted to a new position 2L apart from the left bearing. At the same rotor speed, dynamic reaction on the left bearing in the new arrangement will
Remain same as before
Become equal to 2R
Become equal to R/2
Become equal to R/4
The example of spherical pair is
Bolt and nut
Lead screw of a lathe
Ball and socket joint
Ball bearing and roller bearing
Klein's construction is useful to determine
Velocity of various parts
Acceleration of various parts
Displacement of various parts
Angular acceleration of various parts
For fluctuating loads, well suited bearing is
Ball bearing
Roller bearing
Needle roller bearing
Thrust bearing
The approximate straight line mechanism is a
Four bar linkage
6 bar linkage
8 bar linkage
3 bar linkage
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
An automobile steering gear is an example of
Sliding pair
Rolling pair
Lower pair
Higher pair
The centre of gravity of a coupler link in a four bar mechanism will experience
No acceleration
Only linear acceleration
Only angular acceleration
Both linear and angular acceleration
In multi V-belt transmission, if one of the belt is broken, we have to change the
Broken belt
Broken belt and its adjacent belts
All the belts
There is no need of changing any one as remaining belts can take care of transmission of load
Which of the following is false statement in respect of differences between machine and structure?
Machines transmit mechanical work, whereas structures transmit forces
In machines, relative motion exists between its members, whereas same does not exist in case of structures
Machines modify movement and work, whereas structures modify forces
Efficiency of machines as well as structures is below 100%
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 full depth involute system, the smallest number of teeth in a pinion which meshes with rack without interference is
12
16
25
32
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 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
When brakes are applied to all the four wheels of a moving car, the distance travelled by the car before it is brought to rest, will be
Maximum
Minimum
Zero
None of these
In considering friction of a V-thread, the virtual coefficient of friction (μ₁) is given by
μ₁ = μ sinβ
μ₁ = μ cosβ
μ₁ = μ/sinβ
μ₁ = μ/cosβ
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 two elements of a pair are said to form a higher pair, when they
Have a surface contact when in motion
Have a line or point contact when in motion
Are kept in contact by the action of external forces, when in motion
Permit relative motion
The relation between number of pairs (p) forming a kinematic chain and the number of links (l) is
l = 2p - 2
l = 2p - 3
l = 2p - 4
l = 2p - 5
A torsional system with discs of moment of inertia I₁ and I₂ as shown in the below figure, is gear driven such that the ratio of speed of shaft B to shaft A is 'G'. Neglecting the inertia of gears, the equivalent inertia of disc on shaft B at the speed of shaft A is equal to 
G.I₂
G².I₂
I₂/G
I₂/G²
According to Kennedy's theorem, if three bodies move relatively to each other, their instantaneous centres will lie on a
Straight line
Parabolic curve
Triangle
Rectangle
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
The cam follower generally used in automobile engines is
Knife edge follower
Flat faced follower
Spherical faced follower
Roller follower
A spring controlled governor is said to be isochronous when the controlling force
Increases as the radius of rotation decreases
Increases as the radius of rotation increases
Decreases as the radius of rotation increases
Remain constant for all radii of rotation
The cam and follower is an example of
Sliding pair
Rolling pair
Lower pair
Higher pair
The equivalent length of a simple pendulum which gives the same frequency as a compound pendulum is
h/(kG² + h²)
(kG² + h²)/h
h²/(kG² + h²)
(kG² + h²)/h²
The lower pair is a
Open pair
Closed pair
Sliding pair
Point contact pair
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 motion between a pair when limited to a definite direction, irrespective of the direction of force applied, is known as
Completely constrained motion
Incompletely constrained motion
Successfully constrained motion
None of these
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