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)
m.ω².r cosθ
c.m.ω².r sinθ
(1 - c).m.ω².r (cosθ - sinθ)
m.ω².r (cosθ - sinθ)
Correct Answer :
C. (1 - c).m.ω².r (cosθ - sinθ)
Related Questions
A mechanism consisting of four links is called a __________ mechanism.
Simple
Compound
Binary
None of these
The partial balancing means
Balancing partially revolving masses
Balancing partially reciprocating masses
Best balancing of engines
All of these
The unbalanced force due to reciprocating masses
Varies in magnitude but constant in direction
Varies in direction but constant in magnitude
Varies in magnitude and direction both
Constant in magnitude and direction both
A mechanism is an assemblage of
Two links
Three links
Four or more than four links
All of these
A rotor which is balanced statically but not dynamically is supported on two bearings L apart and at high speed of the rotor, reaction on the left bearing is R. The right side of the bearing is shifted to a new position 2L apart from the left bearing. At the same rotor speed, dynamic reaction on the left bearing in the new arrangement will
Remain same as before
Become equal to 2R
Become equal to R/2
Become equal to R/4
An imaginary circle which by pure rolling action, gives the same motion as the actual gear, is called
Addendum circle
Dedendum circle
Pitch circle
Clearance circle
In a mechanism, usually one link is fixed. If the fixed link is changed in a kinematic chain, then relative motion of other links
Will remain same
Will change
Could change or remain unaltered depending on which link is fixed
Will not occur
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 centrifugal tension in belts
Increases power transmitted
Decreases power transmitted
Have no effect on power transmitted
Increases power transmitted upto a certain speed and then decreases
Which of the following statement is correct for involute gears?
The interference is inherently absent.
The variation in centre distance of shafts increases radial force.
A convex flank is always in contact with concave flank.
The pressure angle is constant throughout the teeth engagement.
Oldhams coupling is an inversion of the kinematic chain used in
Whitworth quick return mechanism
Elliptical trammels
Rotary engine
Universal joint
Which of the following is an inversion of a double slider crank chain?
Oldham's coupling
Elliptical trammel
Scotch yoke mechanism
All of these
Hammer blow
Is the maximum horizontal unbalanced force caused by the mass provided to balance the reciprocating masses.
Is the maximum vertical unbalanced force caused by the mass added to balance the reciprocating masses
Varies as the square root of the speed
Varies inversely with the square of the speed
The periodic time is given by (where ω = Angular velocity of the particle in rad/s)
ω/2π
2π/ω
ω × 2π
π/ω
In full depth involute system, the smallest number of teeth in a pinion which meshes with rack without interference is
12
16
25
32
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
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
Kinematic pairs are those which have
Two elements held together mechanically
Two elements having relative motion
Two elements having Coriolis component
Minimum of two instantaneous centres
The secondary unbalanced force is maximum __________ in one revolution of the crank.
Two times
Four times
Eight times
Sixteen times
If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the latter at the same speed will be
Four times the first one
Same as the first one
One fourth of the first one
One and a half times the first one
If the number of links in a mechanism is equal to l, then the numbers of possible inversions are equal to
l - 2
l - 1
l
l + 1
A chain comprises of 5 links having 5 joints. Is it kinematic chain?
Yes
No
It is a marginal case
Data are insufficient to determine it
The flank of the tooth is the surface of the tooth __________ the pitch surface.
Above
Below
At
None of these
The lower pair is a
Open pair
Closed pair
Sliding pair
Point contact pair
In a cam drive with uniform velocity follower, the sharp corners of the displacement diagram are rounded off at the beginning and at the end of each stroke. This is done
Because of difficulty in manufacturing cam profile
Because of loose contact of follower with cam surface
In order to have acceleration in beginning and retardation at the end of stroke within the finite limits
Because the uniform velocity motion is a partial parabolic motion
In a Hartnell governor, the compression of the spring is __________ the lift of the sleeve.
Equal to
Less than
Greater than
None of these
The axis of precession is __________ to the plane in which the axis of spin is going to rotate.
Parallel
Perpendicular
Both A and B
None of these
A completely constrained motion can be transmitted with.
1 link with pin joints
2 links with pin joints
3 links with pin joints
4 links with pin joints
The amplitude of vibration is always __________ the radius of the circle.
Equal to
Less than
Greater than
None of these
A slider crank chain consists of following numbers of turning and sliding pairs
1, 3
2, 2
3, 1
4, 0