The unbalanced force due to revolving 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
Correct Answer :
B. Varies in direction but constant in magnitude
Related Questions
Critical damping is a function of
Mass and stiffness
Mass and damping coefficient
Mass and natural frequency
Damping coefficient and natural frequency
The direction of Coriolis component of acceleration is the direction
Of relative velocity vector for the two coincident points rotated by 90° in the direction of the angular velocity of the rotation of the link
Along the centripetal acceleration
Along tangential acceleration
Along perpendicular to angular velocity
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
When the pitching of a ship is __________ the effect of gyroscopic couple acting on it will be to move the ship towards port side.
Upward
Downward
Forward
Backward
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
The velocity of the belt for maximum power is (where m = Mass of the belt in kg per metre length)
T/3
(T.g)/3
√(T/3m)
√(3m/T)
In which of the following type of gear train the first gear and the last gear are co-axial.
Simple gear train
Compound gear train
Reverted gear train
None of the above
When the pitching of a ship is upward, the effect of gyroscopic couple acting on it will be
To move the ship towards starboard
To move the ship towards port side
To raise the bow and lower the stern
To raise the stern and lower the bow
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
In order to give a complete secondary balance of a multi-cylinder inline engine,
The algebraic sum of the secondary forces must be equal to zero
The algebraic sum of the couples about any point in the plane of the secondary forces must be equal to zero
Both (A) and (B)
None of these
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
In a pantograph, all the pairs are
Turning pairs
Sliding pairs
Spherical pairs
Self-closed pairs
Which one of the following can completely balance several masses revolving in different planes on a shaft?
A single mass in different planes
Two masses in any two planes
A single mass in one of the planes of the revolving masses
Two equal masses in any two planes
The coefficient of fluctuation of speed is __________ of maximum fluctuation of speed and the mean speed.
Sum
Difference
Product
Ratio
When a ship travels in a sea, which of the effect is more dangerous
Steering
Pitching
Rolling
All of the above
An involute pinion and gear are in mesh. If both have the same size of addendum, then there will be an interference between the
Tip of the gear tooth and flank of pinion
Tip of the pinion and flank of gear
Flanks of both gear and pinion
Tip of both gear and pinion
A thin circular disc is rolling with a uniform linear speed, along a straight path on a plane surface. Which of the following statement is correct in this regard?
All points of the disc have the same velocity
The centre of the disc has zero acceleration
The centre of the disc has centrifugal acceleration
The point on the disc making contact with the plane surface has zero acceleration
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
The sum of the two masses is equal to the total mass of body
The centre of gravity of the two masses coincides with that of the body
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
All of the above
In S.H.M., acceleration is proportional to
Velocity
Displacement
Rate of change of velocity
All of the above
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
The C.G. of a link in any mechanism would experience
No acceleration
Linear acceleration
Angular acceleration
Both angular and linear accelerations
The lower pair is a
Open pair
Closed pair
Sliding pair
Point contact pair
A Porter governor is a
Pendulum type governor
Dead weight governor
Spring loaded governor
Inertia governor
The relation between number of pairs (p) forming a kinematic chain and the number of links (l) is
l = 2p - 2
l = 2p - 3
l = 2p - 4
l = 2p - 5
In S.H.M., the velocity vector w.r.t. displacement vector
Leads by 90°
Lags by 90°
Leads by 180°
Are in phase
The power from the engine to the rear axle of an automobile is transmitted by means of
Worm and worm wheel
Spur gears
Bevel gears
Hooke's joint
The displacement of the D-slide valve is __________ the steam lap by a distance known as lead of the valve.
Greater than
Less than
Equal to
None 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
A universal joint is an example of
Higher pair
Lower pair
Rolling pair
Sliding pair
Elements of pairs held together mechanically is known as
Closed pair
Open pair
Mechanical pair
Rolling pair