In order to give the primary balance of the reciprocating parts of a multi-cylinder inline engines,
The algebraic sum of the primary forces must be equal to zero
The algebraic sum of the couples about any point in the plane of the primary forces must be equal to zero
Both (A) and (B)
None of these
Correct Answer :
C. Both (A) and (B)
Related Questions
Throw of a cam is the maximum distance of the follower from
Base circle
Pitch circle
Root circle
Prime circle
The secondary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is
0° and 90°
180° and 360°
Both (A) and (B)
None of these
A watt's governor can work satisfactorily at speeds from
60 to 80 r.p.m.
80 to 100 r.p.m.
100 to 200 r.p.m.
200 to 300 r.p.m.
Which of the following disciplines provides study of inertia forces arising from the combined effect of the mass and the motion of the parts?
Theory of machines
Applied mechanics
Mechanisms
Kinetics
The absolute acceleration of any point P in a link about center of rotation O is
Along PO
Perpendicular to PO
At 45° to PO
None of the above
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
Which of the following statement is wrong?
A round bar in a round hole form a turning pair
A square bar in a square hole form a sliding pair
A vertical shaft in a foot step bearing forms a successful constraint
All of the above
The frictional torque transmitted in a flat pivot bearing with assumption of uniform pressure is _________ as compared to uniform wear.
Less
More
Same
None of these
The dedendum circle diameter is equal to (where, φ = Pressure angle)
Pitch circle dia. × cosφ
Addendum circle dia. × cosφ
Clearance circle dia. × cosφ
Pitch circle dia. × sinφ
In a coupling rod of a locomotive, each of the four pairs is a ________ pair.
Sliding
Turning
Rolling
Screw
The secondary unbalanced force is __________ the primary unbalanced force.
One-half
Two-third
n times
1/n times
Which of the following statement is correct?
For constant velocity ratio transmission between two gears, the common normal at the point of contact must always pass through a fixed point on the line joining the centres of rotation of gears.
For involute gears, the pressure angle changes with the change in centre distance between gears.
The epicyclic gear trains involve rotation of atleast one gear axis about some other gear axis.
All of the above
A universal joint is an example of
Higher pair
Lower pair
Rolling pair
Sliding pair
In a Hartnell governor, if a spring of greater stiffness is used, then the governor will be
Less sensitive
More sensitive
Unaffected of sensitivity
Isochronous
The relative velocity of B with respect to A in a rigid link AB is
Parallel to AB
Perpendicular to AB
Along AB
At 45° to AB
Which of the following statement is correct?
The power absorbed in operating the piston valve is less than D-slide valve
The wear of the piston valve is less than the wear of the D-slide valve
The D-slide valve is also called outside admission valve.
All of the above
The pressure angle of a cam is the angle between the direction of the follower motion and a normal to the
Pitch circle
Base circle
Pitch curve
Prime circle
Klein's construction can be used when
Crank has a uniform angular velocity
Crank has non-uniform velocity
Crank has uniform angular acceleration
Crank has uniform angular velocity and angular acceleration
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)
ω₁.ω₂.r
(ω₁ - ω₂)r
(ω₁ + ω₂)r
(ω₁ - ω₂)2r
In a screw jack, the effort required to lift the load W is given by (where α = Helix angle, and φ = Angle of friction)
P = W tan(α - φ)
P = W tan(α + φ)
P = W tan(φ - α)
P = W cos(α + φ)
In a rigid link OA, velocity of A w.r.t. O will be
Parallel to OA
Perpendicular to OA
At 45° to OA
Along AO
The Hooke's joint consists of:
Two forks
One fork
Three forks
Four forks
The acceleration of the particle moving with simple harmonic motion is _________ at the mean position.
Zero
Minimum
Maximum
None of these
The ratio of the number of teeth to the pitch circle diameter in millimetres, is called
Circular pitch
Diametral pitch
Module
None of these
Peaucelliers mechanism has
Eight links
Six links
Four links
Twelve links
The maximum efficiency of a screw jack is
(1 - sinφ)/(1 + sinφ)
(1 + sinφ)/(1 - sinφ)
(1 - tanφ)/(1 + tanφ)
(1 + tanφ)/(1 - tanφ)
When the radius of rotation of balls __________ as the equilibrium speed increases, the governor is said to be unstable.
Remains constant
Decreases
Increases
None of these
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
x₁/x₂
log(x₁/x₂)
loge(x₁/x₂)
log(x₁.x₂)
Open pairs are those which have
Point or line contact between the two elements when in motion
Surface contact between the two elements when in motion
Elements of pairs not held together mechanically
Two elements that permit relative motion
Oldham's coupling is the
Second inversion of double slider crank chain
Third inversion of double slider crank chain
Second inversion of single slider crank chain
Third inversion of slider crank chain