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Mechanical Engineering :: Theory of Machine

  1. When the tip of a tooth undercuts the root on its mating gear, it is known as interference.

  2. A.
    Agree
    B.
    Disagree

  3. Under logarithmic decrement, the amplitude of successive vibrations are

  4. A.
    constant
    B.
    in arithmetic progression
    C.
    in geometric progression
    D.
    in logarithmic progression

  5. The efficiency of a screw jack is maximum, when (where α = Helix angle, and φ = Angle of friction)

  6. A.
    α = 45° +
    B.
    α = 45° -
    C.
    α = 90° + φ
    D.
    α = 90° - φ

  7. A fixed gear having 200 teeth is in mesh with another gear having 50 teeth. The two gears are connected by an arm. The number of turns made by the smaller gear for one revolution of arm about the centre of bigger gear is

  8. A.
    2
    B.
    3
    C.
    4
    D.
    5

  9. In a cone pulley, if the sum of radii of the pulleys on the driving and driven shafts is Constant, then

  10. A.
    open belt drive is recommended
    B.
    crossed belt drive is recommended
    C.
    both open belt drive and crossed belt drive is recommended
    D.
    the drive is recommended depending upon the torque transmitted

  11. A flywheel is fitted to the crankshaft of an engine having W as the amount of indicated work per revolution and permissible limits of coefficient of fluctuation of energy and speed as CE and CS respectively. The kinetic energy of the flywheel is given by


  12. When the connection between the elements forming a pair is such that the constrained motion is not completed by itself, but by some other means, the motion is said to be a completely constrained motion,

  13. A.
    Yes
    B.
    No

  14. In gears, interference takes place when

  15. A.
    the tip of a tooth of a mating gear digs into the portion between base and root circles
    B.
    gears do not move smoothly in the absence of lubrication
    C.
    pitch of the gears is not same
    D.
    gear teeth are undercut

  16. The ratio of maximum fluctuation of speed to the mean speed is called

  17. A.
    fluctuation of speed
    B.
    maximum fluctuation of speed
    C.
    coefficient of fluctuation of speed
    D.
    none of these

  18. Which of the following statement is correct for involute gears?

  19. A.
    The interference is inherently absent.
    B.
    The variation in centre distance of shafts increases radial force.
    C.
    A convex flank is always in contact with concave flank.
    D.
    The pressure angle is constant throughout the teeth engagement.