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Mechanical Engineering :: Theory of Machine

  1. The controlling force diagram for a spring controlled governor is a curve passing through the origin.

  2. A.
    Yes
    B.
    No

  3. The lower pairs are __________ pairs.

  4. A.
    self-closed
    B.
    force-closed

  5. The arrangement is called bevel gearing, when two __________ are connected by gears.

  6. A.
    intersecting and coplaner shafts
    B.
    non-intersecting and non-coplaner shafts
    C.
    parallel and coplaner shafts
    D.
    parallel and non-coplaner shafts

  7. The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because, the

  8. A.
    unbalanced couples are caused only at higher speeds
    B.
    unbalanced forces are not dangerous at higher speeds
    C.
    effects of unbalances are proportional to the square of the speed
    D.
    effects of unbalances are directly proportional to the speed

  9. The maximum fluctuation of speed is the

  10. A.
    difference of minimum fluctuation of speed and the mean speed
    B.
    difference of the maximum and minimum speeds
    C.
    sum of maximum and minimum speeds
    D.
    variations of speed above and below the mean resisting torque line

  11. 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)

  12. A.
    l1 = kG
    B.
    l2 = kG
    C.
    l1l2 = kG
    D.
    l1l2 = kG2

  13. A Porter governor is a

  14. A.
    pendulum type governor
    B.
    dead weight governor
    C.
    spring loaded governor
    D.
    inertia governor

  15. 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)

  16. A.
    m2.r sin θ
    B.
    m2.r cos θ
    C.
    m2.r
    D.
    m2.r

  17. A type-writer constitutes a machine.

  18. A.
    Yes
    B.
    No

  19. Due to slip of belt, the velocity ratio of the belt drive increases.

  20. A.
    Yes
    B.
    No