Circular cross section machine parts which are symmetrical about the axis of rotation are made by hot_____________________?

Related Mcqs:

1. High endurance limit of carburised machine parts is because of the fact that carburisation __________________?

   A. Suppresses any stress concentration produced in the parts
   B. Enhances the yield point of the material
   C. Introduces a compressive layer on the surface
   D. Produces a better surface finish

2. The most economical channel section for the fluid flow is the one for which the discharge is maximum for a given cross-sectional area. Vertical velocity distribution in an open channel for laminar flow can be assumed to be_______________?

   A. Parabolic
   B. Hyperbolic
   C. Straight line
   D. None of these

3. An approximately _____________ process exemplifies the flow of a gas through a very long pipe of uniform cross-section ?

   A. Adiabatic
   B. Isothermal
   C. Isentropic
   D. Isochoric

4. Reynolds number of a fluid flowing in a circular pipe is 10,000. What will be the Reynolds number when the fluid velocity is decreased by 30% & the pipe diameter is increased by 30% ?

   A. 9,100
   B. 13,000
   C. 7,000
   D. 2,550

5. Tumbling is the process of improving the ________________ of the materials/parts ?

   A. Surface finish
   B. Fatigue limit
   C. Creep limit
   D. Surface cleanliness

6. Brass parts with high residual tensile stress at the surface are susceptible to season cracking (i.e. spontaneous cracking occuring on exposure to atmospheric corrosion), if its zinc percentage is more than ?

   A. 5
   B. 10
   C. 20
   D. 35

7. The best lubricants for a machine working at high temperature & load is_________________?

   A. Grease
   B. Solid lubricant
   C. Animal oils
   D. Mineral oils

8. Factor of safety in machine design is defined as the ratio of ultimate stress to _____________ stress ?

   A. Working
   B. Bearing
   C. Yield
   D. None of these

9. Dislocation cross-slip is difficult in those materials, which have___________________?

   A. Large number of slip systems
   B. High work hardening rate
   C. Coarse grain size
   D. Low stacking fault energy

10. The pressure drop per unit length for laminar flow of fluid through a long pipe is proportional to (where, A = cross-sectional area of the pipe & D = Diameter of the pipe) ?

    A. A
    B. D
    C. 1/A
    D. 1/A2