The Grubler's criterion for determining the degrees of freedom (n) of a mechanism having plane motion is (where l = Number of links, and j = Number of binary joints)
n = (l -1) - j
n = 2(l - 1) - 2j
n = 3(l - 1) - 2j
n = 4(l - 1) - 3j
Correct Answer :
C. n = 3(l - 1) - 2j
Related Questions
For simple harmonic motion of the of follower, a cosine curve represents
Displacement diagram
Velocity diagram
Acceleration diagram
All of the above
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 the two rotor system as shown in the below figure (I₁ < I₂), a node of vibration is situated 
Between I₁, and I₂ but nearer I₁
Between I₁, and I₂ but nearer to I₂
Exactly in the middle of the shaft
Nearer to I₁ but outside
A higher pair has__________.
Point contact
Surface contact
No contact
None of the above
Which of the following is an example of sliding pair?
Piston and cylinder of a reciprocating steam engine
Shaft with collars at both ends fitted into a circular hole
Lead screw of a lathe with nut
Ball and a socket joint
The radius of a friction circle for a shaft rotating inside a bearing is (where r = Radius of shaft, and tan φ = Coefficient of friction between the shaft and bearing)
r sinφ
r cosφ
r tanφ
(r/2) cosφ
The frictional torque transmitted in a conical pivot bearing with assumption of uniform pressure is __________ as compared to uniform wear.
Less
More
Same
None of these
The maximum fluctuation of speed is the
Difference of minimum fluctuation of speed and the mean speed
Difference of the maximum and minimum speeds
Sum of maximum and minimum speeds
Variations of speed above and below the mean resisting torque line
In elliptical trammels
All four pairs are turning
Three pairs turning and one pair sliding
Two pairs turning and two pairs sliding
One pair turning and three pairs sliding
Which of the following statement is wrong?
The difference between the maximum and minimum energies is called maximum fluctuation of energy
The coefficient of fluctuation of speed is the ratio of maximum fluctuation of speed to the mean speed
The variations of energy above and below the mean resisting torque line is known as fluctuation of energy
None of the above
The inversion of a mechanism is
Changing of a higher pair to a lower pair
Turning its upside down
Obtained by fixing different links in a kinematic chain
Obtained by reversing the input and output motion
The example of spherical pair is
Bolt and nut
Lead screw of a lathe
Ball and socket joint
Ball bearing and roller bearing
A kinematic chain is known as a mechanism when
None of the links is fixed
One of the links is fixed
Two of the links are fixed
None of these
The equation of motion for a vibrating system with viscous damping is (d²x/dt²) + (c/m). (dx/dt) + (s/m). x = 0 If the roots of this equation are real, then the system will be
Over-damped
Under damped
Critically damped
Without vibrations
The example of lower pair is
Shaft revolving in a bearing
Straight line motion mechanisms
Automobile steering gear
All of the above
In a turning moment diagram, the variations of energy above and below the mean resisting torque line is called
Fluctuation of energy
Maximum fluctuation of energy
Coefficient of fluctuation of energy
None of these
To obviate axial thrust, following gear drive is used
Double helical gears having opposite teeth
Double helical gears having identical teeth
Single helical gear in which one of the teeth of helix angle a is more
Mutter gears
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
Minimum number of teeth for involute rack and pinion arrangement for pressure angle of 20° is
18
20
30
34
Lower 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
A shaft has two heavy rotors mounted on it. The transverse natural frequencies, considering each of the rotor separately, are 100 Hz and 200 Hz respectively. The lowest critical speed is
5,367 r.p.m.
6,000 r.p.m.
9,360 r.p.m.
12,000 r.p.m.
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 stress induced in a body will be shear stress, when it is subjected to
Longitudinal vibrations
Transverse vibrations
Torsional vibrations
None of these
The dynamic friction is the friction experienced by a body, when the body
Is in motion
Is at rest
Just begins to slide over the surface of the other body
None of the above
Which of the following is an open pair?
Ball and socket joint
Journal bearing
Lead screw and nut
Cam and follower
Which of the following is an inversion of Single slider crank chain?
Beam engine
Rotary engine
Oldhams coupling
Elliptical trammel
Which of the following property of the instantaneous centre is correct?
A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.
The two rigid links have no linear velocity relative to each other at the instantaneous centre.
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.
All of the above
In a steam engine, one method of obtaining the earlier cut-off with a simple slide valve is by increasing the angle of advance of the eccentric while the throw of the eccentric, steam lap and exhaust lap are kept constant. This method will
Cause withdrawing or throttling of steam
Reduce length of effective stroke of piston
Reduce maximum opening of port to steam
All of these
The frequency of oscillation of a torsional pendulum is
2πk/r. √(g/l)
r/2πk. √(l/g)
2πr/k. √(g/l)
r/2πk. √(g/l)
A Hartnell governor is a
Dead weight governor
Pendulum type governor
Spring loaded governor
Inertia governor