Home
Current Affairs January 2024

What is the correct answer?

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

Correct Answer :

B. Between I₁, and I₂ but nearer to I₂


Related Questions

What is the correct answer?

4

The coriolis component of acceleration exists whenever a point moves along a path that has

A. Linear displacement

B. Rotational motion

C. Gravitational acceleration

D. Tangential acceleration

What is the correct answer?

4

The critical speed of a shaft in revolution per second is __________ as that of natural frequency of transverse vibration.

A. Same

B. Different

C. Unpredictable

D. None of these

What is the correct answer?

4

It is required to connect two parallel shafts, the distance between whose axes is small and variable. The shafts are coupled by

A. Universal joint

B. Knuckle joint

C. Oldham's coupling

D. Flexible coupling

What is the correct answer?

4

Which of the following has sliding motion?

A. Crank

B. Connecting rod

C. Crank pin

D. Crosshead

What is the correct answer?

4

In a Hartnell governor, the lift of the sleeve is given by (where r₁ and r₂ = Max. and min. radii of rotation, x = Length of ball arm of the lever, and y = Length of sleeve arm of the lever)

A. (r₁ + r₂) (y/x)

B. (r₁ + r₂) (x/y)

C. (r₁ - r₂) (y/x)

D. (r₁ - r₂) (x/y)

What is the correct answer?

4

The balancing of a rigid rotor can be achieved by appropriately placing balancing masses in

A. A single plane

B. Two planes

C. Three planes

D. Four planes

What is the correct answer?

4

The velocity of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by

A. ωR cosθ

B. ω(R - r₁) cosθ

C. ω(R - r₁) sinθ

D. ωr₁ sinθ

What is the correct answer?

4

To transmit power from one rotating shaft to another whose axes are neither parallel nor intersecting, use?

A. Spur gear

B. Spiral gear

C. Bevel gear

D. Worm gear

What is the correct answer?

4

The danger of breakage and vibration is maximum

A. Below the critical speed

B. Near the critical speed

C. Above the critical speed

D. None of these

What is the correct answer?

4

There are six gears A, B, C, D, E and F in a compound train. The numbers of teeth in the gears are 20, 60, 30, 80, 25 and 75 respectively. The ratio of angular speeds of the driven (F) to the driver (A) of the drive is

A. 1/24

B. 1/8

C. 4/15

D. 12

What is the correct answer?

4

A reed type tachometer use the principle of

A. Longitudinal vibration

B. Torsional vibration

C. Transverse vibration

D. Damped free vibration

What is the correct answer?

4

Which of the following statement is correct for gears?

A. The addendum is less than the dedendum

B. The pitch circle diameter is the product of module and number of teeth

C. The contact ratio means the number of pairs of teeth in contact

D. All of the above

What is the correct answer?

4

The effort of a Porter governor is equal to (where c = Percentage increase in speed, m = Mass of ball, and M = Mass on the sleeve)

A. c (m - M) g

B. c (m + M) g

C. c/(m + M) g

D. c/(m - M) g

What is the correct answer?

4

When the axes of the first and last wheels are coaxial, then the train is known as

A. Simple train of wheels

B. Compound train of wheels

C. Reverted gear train

D. Epicyclic gear train

What is the correct answer?

4

If the opposite links of a four bar linkage are equal, the links will always form a

A. Triangle

B. Rectangle

C. Parallelogram

D. Pentagon

What is the correct answer?

4

When there is a reduction in amplitude over every cycle of vibration, then the body is said to have

A. Free vibration

B. Forced vibration

C. Damped vibration

D. Under damped vibration

What is the correct answer?

4

The lower pairs are __________ pairs.

A. Self-closed

B. Force-closed

C. Friction closed

D. None of these

What is the correct answer?

4

The Coriolis component of acceleration acts

A. Along the sliding surface

B. Perpendicular to the sliding surface

C. At 45° to the sliding surface

D. Parallel to the sliding surface

What is the correct answer?

4

The power of a Porter governor is equal to

A. [c²/(1 + 2c)] (m + M) g.h

B. [2c²/(1 + 2c)] (m + M) g.h

C. [3c²/(1 + 2c)] (m + M) g.h

D. [4c²/(1 + 2c)] (m + M) g.h

What is the correct answer?

4

Which of the following mechanisms produces mathematically an exact straight line motion?

A. Grasshopper mechanism

B. Watt mechanism

C. Peaucellier's mechanism

D. Tchebicheff mechanism

What is the correct answer?

4

The secondary 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)

A. m.ω².r sinθ

B. m.ω².r cosθ

C. m.ω².r (sin 2θ/n)

D. m.ω².r (cos 2θ/n)

What is the correct answer?

4

The included angle for the V-belt is usually

A. 10° to 20°

B. 20° to 30°

C. 30° to 40°

D. 60° to 80°

What is the correct answer?

4

The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (θ) is equal to

A. 90° and 180°

B. 45° and 225°

C. 180° and 270°

D. 270° and 360°

What is the correct answer?

4

The power from the engine to the rear axle of an automobile is transmitted by means of

A. Worm and worm wheel

B. Spur gears

C. Bevel gears

D. Hooke's joint

What is the correct answer?

4

In which of the following type of gear train the first gear and the last gear are co-axial.

A. Simple gear train

B. Compound gear train

C. Reverted gear train

D. None of the above

What is the correct answer?

4

Instantaneous center of rotation of a link in a four bar mechanism lies on

A. Right side pivot of this link

B. Left side pivot of this link

C. A point obtained by intersection on extending adjoining links

D. Cant occur

What is the correct answer?

4

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)

A. ω √(x² - r²)

B. ω √(r² - x²)

C. ω² √(x² - r²)

D. ω² √(r² - x²)

What is the correct answer?

4

The unbalanced force due to revolving masses

A. Varies in magnitude but constant in direction

B. Varies in direction but constant in magnitude

C. Varies in magnitude and direction both

D. Constant in magnitude and direction both

What is the correct answer?

4

The engine of an aeroplane rotates in clockwise direction when seen from the tail end and the aeroplane takes a turn to the left. The effect of gyroscopic couple on the aeroplane will be

A. To dip the nose and tail

B. To raise the nose and tail

C. To raise the nose and dip the tail

D. To dip the nose and raise the tail

What is the correct answer?

4

The method of direct and reverse cranks is used in engines for

A. The control of speed fluctuations

B. Balancing of forces and couples

C. Kinematic analysis

D. Vibration analysis