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4

The centre distance between two meshing involute gears is equal to

A. Sum of base circle radii/cosφ

B. Difference of base circle radii/ cosφ

C. Sum of pitch circle radii/ cosφ

D. Difference of pitch circle radii/ cosφ

Correct Answer :

A. Sum of base circle radii/cosφ


Related Questions

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4

In higher pair, the relative motion is

A. Purely turning

B. Purely sliding

C. Purely rotary

D. Combination of sliding and turning

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4

When a body is subjected to transverse vibrations, the stress induced in a body will be

A. Shear stress

B. Bending stress

C. Tensile stress

D. Compressive stress

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4

In a reciprocating steam engine, when the crank has turned from inner dead centre through an angle θ, the angular velocity of the connecting rod is given by

A. ω sinθ/(n² - sin²θ)1/2

B. ω cosθ/(n² - cos²θ)1/2

C. ω sinθ/(n² - cos²θ)1/2

D. ω cosθ/(n² - sin²θ)1/2

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4

A Hartnell governor is a

A. Dead weight governor

B. Pendulum type governor

C. Spring loaded governor

D. Inertia governor

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4

In under damped vibrating system, if x₁ and x₂ are the successive values of the amplitude on the same side of the mean position, then the logarithmic decrement is equal to

A. x₁/x₂

B. log(x₁/x₂)

C. loge(x₁/x₂)

D. log(x₁.x₂)

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4

The two links OA and OB are connected by a pin joint at O. If the link OA turns with angular velocity ω₁ rad/s in the clockwise direction and the link OB turns with angular velocity ω₂ rad/s in the clockwise direction, then the rubbing velocity at the pin joint O is (where r = Radius of the pin at O)

A. ω₁.ω₂.r

B. (ω₁ - ω₂)r

C. (ω₁ + ω₂)r

D. (ω₁ - ω₂)2r

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4

The frictional torque transmitted in a flat collar bearing, considering uniform wear, is (where r₁ and r₂ = External and internal radii of collar respectively)

A. (1/2) μ W (r₁ + r₂)

B. (2/3) μ W (r₁ + r₂)

C. (1/2) μ W [(r₁³ - r₂³)/(r₁² - r₂²)]

D. (2/3) μ W [(r₁³ - r₂³)/(r₁² - r₂²)]

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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

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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

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4

When the radius of rotation of balls __________ as the equilibrium speed increases, the governor is said to be unstable.

A. Remains constant

B. Decreases

C. Increases

D. None of these

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4

Kinematic pairs are those which have

A. Point or line contact between the two elements when in motion

B. Surface contact between the two elements when in motion

C. Elements of pairs not held together mechanically

D. Two elements that permit relative motion

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4

The mechanism consisting of three turning pairs and one sliding pair, is called a

A. Single slider crank chain

B. Whitworth quick return motion mechanism

C. Crank and slotted lever quick return motion mechanism

D. All of the above

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4

In a locomotive, the resultant unbalanced force due to the two cylinders along the line of stroke, is known as

A. Tractive force

B. Swaying couple

C. Hammer blow

D. None of these

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4

The indicator using Watt mechanism is known as

A. Thompson indicator

B. Richard indicator

C. Simplex indicator

D. Thomson indicator

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4

In a band and block brake, the ratio of tensions on tight side and slack side of the band is (where μ = Coefficient of friction between the blocks and the drum, θ = Semi-angle of each block subtending at the centre of drum, and n = Number of blocks)

A. T₁/T₂ = μ. θ. n

B. T₁/T₂ = [(1 - μ tanθ)/(1 + μ tanθ)]n

C. T₁/T₂ = (μ θ)n

D. T₁/T₂ = [(1 + μ tanθ)/(1 - μ tanθ)]n

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4

Pitch point of a cam is

A. A point on the pitch curve having minimum pressure angle

B. A point on the pitch curve having maximum pressure angle

C. Any point on the pitch curve

D. Any point on the pitch circle

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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

The tractive force in a locomotive with two cylinders is given by (where c = Fraction of reciprocating parts per cylinder, m = Mass of reciprocating parts, ω = Angular speed of crank, r = Radius of crank, and θ = Angle of inclination of crank to the line of stroke)

A. m.ω².r cosθ

B. c.m.ω².r sinθ

C. (1 - c).m.ω².r (cosθ - sinθ)

D. m.ω².r (cosθ - sinθ)

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4

In the below figure, PC is the connecting rod and OC is the crank making an angle θ with the line of stroke PO and rotates with uniform angular velocity at ω rad/s. The Klien's acceleration diagram for determining the acceleration of the piston P is shown by quadrilateral CQNO. The acceleration of the piston P with respect to the crankpin C is given by

A. ω² × NO

B. ω² × CO

C. ω² × CN

D. ω² × QN

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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

Pitch point on a cam is

A. Any point on pitch curve

B. The point on cam pitch curve having the maximum pressure angle

C. Any point on pitch circle

D. The point on cam pitch curve having the minimum pressure angle

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4

The frequency of oscillation at compared to earth will be

A. 6 times more

B. 6 times less

C. 2.44 times more

D. 2.44 times less

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4

The frictional torque transmitted in a flat pivot bearing with assumption of uniform pressure is _________ as compared to uniform wear.

A. Less

B. More

C. Same

D. None of these

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4

Which of the following is an inversion of a single slider crank chain?

A. Pendulum pump

B. Oscillating cylinder engine

C. Rotary internal combustion engine

D. All of these

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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

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4

In a steam engine, the distance by which the outer edge of the Dslide valve overlaps the steam port is called

A. Lead

B. Steam lap

C. Exhaust lap

D. None of these

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4

The secondary unbalanced force is maximum __________ in one revolution of the crank.

A. Two times

B. Four times

C. Eight times

D. Sixteen times

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4

The frictional torque transmitted by a cone clutch is same as that of

A. Flat pivot bearing

B. Flat collar bearing

C. Conical pivot bearing

D. Truncated conical pivot bearing

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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

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4

The coriolis component of acceleration depends upon

A. Velocity of slider

B. Angular velocity of the link

C. Both (A) and (B)

D. None of these