Home
Current Affairs January 2024

What is the correct answer?

4

The primary unbalanced force is maximum _________ in one revolution of the crank.

A. Twice

B. Four times

C. Eight times

D. Sixteen times

Correct Answer :

A. Twice


Related Questions

What is the correct answer?

4

The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as

A. Damping factor

B. Damping coefficient

C. Logarithmic decrement

D. Magnification factor

What is the correct answer?

4

A chain comprises of 5 links having 5 joints. Is it kinematic chain?

A. Yes

B. No

C. It is a marginal case

D. Data are insufficient to determine it

What is the correct answer?

4

A rigid body, under the action of external forces, can be replaced by two masses placed at a fixed distance apart. The two masses form an equivalent dynamical system, if

A. The sum of the two masses is equal to the total mass of body

B. The centre of gravity of the two masses coincides with that of the body

C. The sum of mass moment of inertia of the masses about their centre of gravity is equal to the mass moment of inertia of the body

D. All of the above

What is the correct answer?

4

The centre of percussion is below the centre of gravity of the body and is at a distance equal to

A. h/kG

B. h²/kG

C. kG²/h

D. h × kG

What is the correct answer?

4

Inertia force acts

A. Perpendicular to the acceleration force

B. Along the direction of acceleration force

C. Opposite to the direction of acceleration force

D. None of the above

What is the correct answer?

4

In a turning moment diagram, the variations of energy above and below the mean resisting torque line is called

A. Fluctuation of energy

B. Maximum fluctuation of energy

C. Coefficient of fluctuation of energy

D. None of these

What is the correct answer?

4

In a locomotive, the maximum magnitude of the unbalanced force along the perpendicular to the line of stroke, is known as

A. Tractive force

B. Swaying couple

C. Hammer blow

D. None of these

What is the correct answer?

4

Elements of pairs held together mechanically is known as

A. Closed pair

B. Open pair

C. Mechanical pair

D. Rolling pair

What is the correct answer?

4

The rotating shafts tend to vibrate violently at whirling speeds because

A. The system is unbalanced

B. Bearing centre line coincides with the axis

C. The shafts are rotating at very high speeds

D. Resonance is caused due to the heavy mass of the rotor

What is the correct answer?

4

In order to give the primary balance of the reciprocating parts of a multi-cylinder inline engines,

A. The algebraic sum of the primary forces must be equal to zero

B. The algebraic sum of the couples about any point in the plane of the primary forces must be equal to zero

C. Both (A) and (B)

D. None of these

What is the correct answer?

4

At the nodal point in a shaft, the amplitude for torsional vibration will be

A. Minimum

B. Maximum

C. Zero

D. Infinity

What is the correct answer?

4

When a slider moves on a fixed link having curved surface, their instantaneous centre lies

A. On their point of contact

B. At the centre of curvature

C. At the centre of circle

D. At the pin joint

What is the correct answer?

4

An exact straight line motion mechanism is a

A. Scott-Russell's mechanism

B. Hart's mechanism

C. Peaucellier's mechanism

D. All of these

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 indicator using Watt mechanism is known as

A. Thompson indicator

B. Richard indicator

C. Simplex indicator

D. Thomson indicator

What is the correct answer?

4

Throw of a cam is the maximum distance of the follower from

A. Base circle

B. Pitch circle

C. Root circle

D. Prime circle

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

What is the correct answer?

4

The frictional torque transmitted in a flat pivot bearing, considering uniform wear, is (where μ = Coefficient of friction, W = Load over the bearing, and R = Radius of bearing surface)

A. (1/2) μ W R

B. (2/3) μ W R

C. (3/4) μ W R

D. μ W R

What is the correct answer?

4

Klein's construction can be used when

A. Crank has a uniform angular velocity

B. Crank has non-uniform velocity

C. Crank has uniform angular acceleration

D. Crank has uniform angular velocity and angular acceleration

What is the correct answer?

4

A cam mechanism imparts following motion

A. Rotating

B. Oscillating

C. Reciprocating

D. All of the above

What is the correct answer?

4

A rigid body possesses ________degrees of freedom

A. One

B. Two

C. Four

D. Six

What is the correct answer?

4

The Hooke's joint consists of:

A. Two forks

B. One fork

C. Three forks

D. Four forks

What is the correct answer?

4

In a circular arc cam with roller follower, the acceleration in any position of the lift will depend only upon

A. Total lift, total angle of lift, minimum radius of cam and cam speed

B. Radius of circular arc, cam speed, location of centre of circular arc and roller diameter

C. Mass of cam follower linkage, spring stiffness and cam speed

D. Total lift, centre of gravity of the cam and cam speed

What is the correct answer?

4

In order to double the period of a simple pendulum, the length of the string should be

A. Halved

B. Doubled

C. Quadrupled

D. None of these

What is the correct answer?

4

The relation between number of pairs (p) forming a kinematic chain and the number of links (l) is

A. l = 2p - 2

B. l = 2p - 3

C. l = 2p - 4

D. l = 2p - 5

What is the correct answer?

4

The C.G. of a link in any mechanism would experience

A. No acceleration

B. Linear acceleration

C. Angular acceleration

D. Both angular and linear accelerations

What is the correct answer?

4

When two pulleys are connected by means of a cross belt drive, then both the pulleys will rotate in __________ directions.

A. Same

B. Opposite

C. Perpendicular

D. None of these

What is the correct answer?

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

What is the correct answer?

4

Which of the following property of the instantaneous centre is correct?

A. A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.

B. The two rigid links have no linear velocity relative to each other at the instantaneous centre.

C. The velocity of the instantaneous centre relative to any third rigid link is same whether the instantaneous centre is regarded as a point on the first rigid link or on the second rigid link.

D. All of the above

What is the correct answer?

4

The frictional torque transmitted in a flat pivot bearing, considering uniform pressure, is (where μ = Coefficient of friction, W = Load over the bearing, and R = Radius of bearing surface)

A. (1/2) μ W R

B. (2/3) μ W R

C. (3/4) μ W R

D. μ W R