logo

CuriousTab

CuriousTab

Discussion


Home Mechanical Engineering Theory of machines Comments

  • Question
  • If ?/?n is very high for a body vibrating under steady state vibrations, the phase angle for all values of damping factors, will tend to approach


  • Options
  • A. 0°
  • B. 90°
  • C. 180°
  • D. 360°

  • Correct Answer
  • 180° 


  • Theory of machines problems


    Search Results


    • 1. The ratio of the actual damping coefficient to the critical damping coefficient is called damping factor.

    • Options
    • A. Yes
    • B. No
    • Discuss
    • 2. The acceleration of the particle moving with simple harmonic motion is inversely proportional to the displacement of the particle from the mean position.

    • Options
    • A. Yes
    • B. No
    • Discuss
    • 3. The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (?) is equal to

    • Options
    • A. 90° and 180°
    • B. 45° and 225°
    • C. 180° and 270°
    • D. 270° and 360°
    • Discuss
    • 4. When the two elements of a pair have a surface contact when relative motion takes place and the surface of one element slides over the surface of the other, the pair formed is known as a

    • Options
    • A. lower pair
    • B. higher pair
    • C. self-closed pair
    • D. force-closed pair
    • Discuss
    • 5. Whitworth quick return motion mechanism consists of three turning pairs and one sliding pair.

    • Options
    • A. Right
    • B. Wrong
    • Discuss
    • 6. The tractive force in a locomotive with two cylinders is given by (where c = Fraction of reciprocating parts per cylinder, m = Mass of reciprocating parts, ? = Angular speed of crank, r = Radius of crank, and ? = Angle of inclination of crank to the line of stroke)

    • Options
    • A. m.?2.r cos ?
    • B. c.m.?2.r sin ?
    • C. (1 - c)m.?2.r(cos ? - sin ?)
    • D. m.?2.r(cos ? - sin ?)
    • Discuss
    • 7. In railway axle boxes, the bearing used is

    • Options
    • A. deep groove ball bearing
    • B. double row self-aligning ball bearing
    • C. double row spherical roller bearing
    • D. cylindrical roller bearing
    • Discuss
    • 8. In order to give the primary balance of the reciprocating parts of a multi-cylinder in-line engines,

    • Options
    • A. the algebraic sum of the primary forces must be equal to zero
    • B. the algebraic sum of the couples about any point in the plane of the primary forces must be equal to zero
    • C. both (a) and (b)
    • D. none of these
    • Discuss
    • 9. When a particle moves round the circumference of a circle of radius r with ? rad/s, then its maximum acceleration is ?2r.

    • Options
    • A. Right
    • B. Wrong
    • Discuss
    • 10. The centre distance between two meshing involute gears is equal to

    • Options
    • A.
    • B.
    • C.
    • D.
    • Discuss


    Comments

    There are no comments.

Enter a new Comment