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4

The equation of motion for a single degree of freedom system with viscous damping is 4(dx²/dt²) + 9(dx/dt) + 16x. The damping ratio of the system is

A. 9/8

B. 9/82

C. 9/16

D. 9/128

Correct Answer :

C. 9/16


Related Questions

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4

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)

A. 0.4985/√δ

B. 0.5615/√δ

C. 0.571/√δ

D. 0.6253/√δ

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4

The axis of precession is __________ to the plane in which the axis of spin is going to rotate.

A. Parallel

B. Perpendicular

C. Both A and B

D. None of these

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4

The length of a simple pendulum which gives the same frequency as the compound pendulum, is

A. kG + l₁

B. kG² + l₁

C. (kG² + l₁²)/ l₁

D. (kG + l₁²)/ l₁

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4

The minimum force required to slide a body of weight W on a rough horizontal plane is

A. W sinθ

B. W cosθ

C. W tanθ

D. W cosecθ

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4

Which of the following is an inversion of Single slider crank chain?

A. Beam engine

B. Rotary engine

C. Oldhams coupling

D. Elliptical trammel

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4

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

A. (l₁ + l₂ + l₃)/3

B. l = l₁ + l₂.(d₁/d₂)³ + l₂.(d₁/d₃)³

C. l = l₁ + l₂.(d₁/d₂)⁴ + l₃.(d₁/d₃)⁴

D. l₁ + l₂ + l₃

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4

In steady state forced vibrations, the amplitude of vibrations at resonance is __________ damping coefficient.

A. Equal to

B. Directly proportional to

C. Inversely proportional to

D. Independent of

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4

Two pulleys of radii r₁ and r₂ and at distance x apart are connected by means of an open belt drive. The length of the belt is

A. π (r₁ + r₂) + (r₁ + r₂)²/x + 2x

B. π (r₁ + r₂) + (r₁ - r₂)²/x + 2x

C. π (r₁ - r₂) + (r₁ - r₂)²/x + 2x

D. π (r₁ - r₂) + (r₁ + r₂)²/x + 2x

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4

In a shaper mechanism, the Coriolis component of acceleration will

A. Not exist

B. Exist

C. Depend on position of crank

D. None of the above

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4

The Bifilar suspension method is used to determine

A. Natural frequency of vibration

B. Position of balancing weights

C. Moment of inertia

D. Centripetal acceleration

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4

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

A. 2

B. 3

C. 4

D. 5

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4

In its simplest form, a cam mechanism consists of following number of links

A. 1

B. 2

C. 3

D. 4

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4

The primary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is

A. 0° and 90°

B. 0° and 180°

C. 90° and 180°

D. 180° and 360°

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4

Which of the following is an example of sliding pair?

A. Piston and cylinder of a reciprocating steam engine

B. Shaft with collars at both ends fitted into a circular hole

C. Lead screw of a lathe with nut

D. Ball and a socket joint

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4

In a four stroke I.C. engine, the turning moment during the compression stroke is

A. Positive throughout

B. Negative throughout

C. Positive during major portion of the stroke

D. Negative during major portion of the stroke

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4

A body in motion will be subjected to coriolis acceleration when that body is

A. In plane rotation with variable velocity

B. In plane translation with variable velocity

C. In plane motion which is a resultant of plane translation and rotation

D. Restrained to rotate while sliding over another body

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4

The component of the acceleration, parallel to the velocity of the particle, at the given instant is called

A. Radial component

B. Tangential component

C. Coriolis component

D. None of these

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4

The lead screw of a lathe with nut forms a

A. Rolling pair

B. Sliding pair

C. Screw pair

D. Turning pair

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4

In a mechanism, the fixed instantaneous centres are those centres which

A. Remain in the same place for all configurations of the mechanism

B. Vary with the configuration of the mechanism

C. Moves as the mechanism moves, but joints are of permanent nature

D. None of the above

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4

The example of lower pair is

A. Shaft revolving in a bearing

B. Straight line motion mechanisms

C. Automobile steering gear

D. All of the above

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4

The maximum fluctuation of speed is the

A. Difference of minimum fluctuation of speed and the mean speed

B. Difference of the maximum and minimum speeds

C. Sum of maximum and minimum speeds

D. Variations of speed above and below the mean resisting torque line

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4

Governor is used in automobile to

A. Decrease the variation of speed

B. Maximize the fuel economy

C. Limit the vehicle speed

D. Maintain constant engine speed

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4

The sense of coriolis component 2 ωv is same as that of the relative velocity vector v rotated at

A. 45° in the direction of rotation of the link containing the path

B. 45° in the direction opposite to the rotation of the link containing the path

C. 90° in the direction of rotation of the link containing the path

D. 180° in the direction opposite to the rotation of the link containing the path

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4

A Porter governor is a

A. Pendulum type governor

B. Dead weight governor

C. Spring loaded governor

D. Inertia governor

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4

A spring controlled governor is said to be isochronous when the controlling force

A. Increases as the radius of rotation decreases

B. Increases as the radius of rotation increases

C. Decreases as the radius of rotation increases

D. Remain constant for all radii of rotation

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4

A mechanism consisting of four links is called a __________ mechanism.

A. Simple

B. Compound

C. Binary

D. None of these

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4

A shaft carrying three rotors will have

A. No node

B. One node

C. Two nodes

D. Three nodes

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4

In the two rotor system as shown in the below figure (I₁ < I₂), a node of vibration is situated

A. Between I₁, and I₂ but nearer I₁

B. Between I₁, and I₂ but nearer to I₂

C. Exactly in the middle of the shaft

D. Nearer to I₁ but outside

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4

When the two elements of a pair have __________ when in motion, it is said to a lower pair.

A. Line or point contact

B. Surface contact

C. Body contact

D. None of these

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4

The frequency of damped vibrations with viscous damping is ________ the frequency of undamped vibrations.

A. More than

B. Less than

C. Same as

D. None of these