74701. When a point at the end of a link moves with constant angular velocity, its acceleration will have
74702. The time taken by a particle for one complete oscillationis known as periodic time.
74703. 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
74704. In a steam engine, the earlier cut-off with a simple slide valve may be obtained by increasing the angle of advance of the eccentric but reducing the throw of the eccentric and keeping the steam lap and exhaust lap constant. This method will cause withdrawing or throttling of steam.
74705. A governor is said to be stable, if the
74706. In a Proell governor, the balls are attached to the extension of lower links.
74707. A point B on a rigid link AB moves with respect to A with angular velocity ω rad/s. The radial component of the acceleration of B with respect to A, is (where vBA = Linear velocity of B with respect to A)
74708. Critical damping is a function of
74709. The relation between me number of links (l) and the number of binary joints (j) for a kinematic chain having constrained motion is given by l = l - 2. If the left hand side of this equation is greater than the right hand side, then the chain is
74710. A Porter governor can not be isochronous.
74711. The example of successfully constrained motion is a
74712. Which one of the following can completely balance several masses revolving in different planes on a shaft?
74713. When a shaking force is transmitted through the springs, damping becomes detrimental when the ratio of its frequency to the natural frequency is greater than
74714. When the nature of contact between the elements of a pair is such that it can turn or revolve about a fixed axis, the pair is known as a rolling pair.
74715. Creep in belt drive is due to
74716. A watt's governor can work satisfactorily at speeds from
74717. The displacement of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by (where R = Radius of flank, r1 = Minimum radius of the cam, and θ = Angle turned through by the cam)
74718. 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 C Q NO, the acceleration of the piston is zero when the crank OC and connecting rod PC are at right angles to each other.
74719. An exact straight line motion mechanism is a
74720. A body of weight W is required to move up the rough inclined plane whose angle of inclination with the horizontal is α. The effort applied parallel to the plane is given by (where μ = tan φ = Coefficient of friction between the plane and the body)
74721. When the sleeve of a Porter governor moves downwards, the governor speed
74722. When one of the links of a kinematic chain is fixed, the chain is known as a
74723. The natural frequency of free transverse vibrations of a shaft fixed at both ends and carrying a uniformly distributed load is 0.571/δS , where δS is the static deflection of a shaft fixed at both ends and carrying a uniformly distributed load.
74724. When brakes are applied to all the four wheels of a moving car, the distance travelled by the car before it is brought to rest, will be
74725. In a steam engine, the distance by which the outer edge of the D-slide valve overlaps the steam port is called
74726. The controlling force diagram for a spring controlled governor is a curve passing through the origin.
74727. The lower pairs are __________ pairs.
74728. The arrangement is called bevel gearing, when two __________ are connected by gears.
74729. The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because, the
74730. The maximum fluctuation of speed is the
74731. The essential condition of placing the two masses, so that the system becomes dynamically equivalent, is (where l1 and l2 = Distance of two masses from the centre of gravity of the body, and kG = Radius of gyration of the body)
74732. A Porter governor is a
74733. The secondary unbalanced force due to inertia of reciprocating parts in a reciprocating engine is given by (where m = Mass of reciprocating parts, ω = Angular speed of crank, r = Radius of crank, θ = Angle of inclination of crank with the line of stroke, and n = Ratio of the lengm of connecting rod to radius of crank)
74734. A type-writer constitutes a machine.
74735. Due to slip of belt, the velocity ratio of the belt drive increases.
74736. In steady state forced vibrations, the amplitude of vibrations at resonance is __________ damping coefficient.
74737. A body in motion will be subjected to coriolis acceleration when that body is
74738. The rolling of a complete ship side-ways is known as pitching of a ship.
74739. The frictional torque transmitted by a disc or plate clutch is same as that of
74740. The frictional torque transmitted by a cone clutch is same as that of
74741. When two non-intersecting and non-coplaner shafts are connected by gears, the arrangement is known as helical gearing.
74742. When the elements of a pair are kept in contact by the action of external forces, the pair is said to be a