Home / Mechanical Engineering / Theory of Machine :: Section 4

Mechanical Engineering :: Theory of Machine

  1. In vibration isolation system, if ω/ωn > 2, then for all values of damping factor, the trans-missibility (i.e. the ratio of the force transmitted to the force applied) will be less than unity.

  2. A.
    True
    B.
    False

  3. Two pulleys of radii r1 and r2 and at distance x apart are connected by means of a cross belt drive. The length of the belt is


  4. The acceleration of the reciprocating roller follower when it has contact with the straight flanks of the tangent cam, is given by

  5. A.
    ω2(r1 - r2)(1 - cos2θ)
    B.
    ω2(r1 + r2)(1 + cos2θ)
    C.
    ω2(r1 + r2)
    D.
    ω2(r1 - r2)(1 - sin2 θ)

  6. For the brake to be self locking, the force P at C shown in the below figure, should

  7. A.
    be zero
    B.
    act in upward direction
    C.
    act in downward direction
    D.
    none of these

  8. In a four bar chain or quadric cycle chain

  9. A.
    each of the four pairs is a turning pair
    B.
    one is a turning pair and three are sliding pairs
    C.
    two are turning pairs and two are sliding pairs
    D.
    three are turning pairs and one is a sliding pair

  10. A single degree of freedom system is given by , with usual notations. It represents

  11. A.
    free vibration with damping
    B.
    free vibration without damping
    C.
    forced vibration with damping
    D.
    forced vibration without damping

  12. In a Hartnell governor, the lift of the sleeve is given by (where r1 and r2 = Max. and min. radii of rotation, x = Length of ball arm of the lever, and y = Length of sleeve arm of the lever)

  13. A.
    (r1 + r2)
    B.
    (r1 + r2)
    C.
    (r1 - r2)
    D.
    (r1 - r2)

  14. The maximum efficiency of a screw jack is


  15. When a mechanism is required to transmit power or to do some particular type of work, then it becomes a machine.

  16. A.
    Agree
    B.
    Disagree

  17. The transmissibility, for all values of damping factor, will be less than unity, if ω/ωn is

  18. A.
    equal to 1
    B.
    less than 2
    C.
    equal to 2
    D.
    greater than 2