Identify the false statement?

Related Mcqs:

1. Identify the correct statement with reference to the extractive metallurgy of aluminium ?

   A. The electrolyte consists of molten Na3AlF6 with approximately 1 to 8% Al2O3
   B. Approximately 80% of the aluminium deposited on the cathode comes from cryolite
   C. Sodium is deposited along with aluminium, but is immediately vaporised
   D. Anode effect sets in when the cryolite concentration goes below 40%.

2. Pick out the wrong statement ?

   A. Both annealing and normalising release the internal stresses of the material besides improving
   the mechanical properties
   B. Low carbon steel does not respond to the heat treatment for hardening of the material, hence it
   is subjected to case hardening or surface hardening processes like cyaniding, carburising,
   nitriding etc., which produces high carbon outer layers resulting in increase of surface
   hardness
   C. Induction hardening and flame hardening techniques are also used for surface hardening
   D. Martempering of a material is a hardening process

3. In extrusion of metals, which of the following statement is true ?

   A. Speed of the extruded material is same as that of ram speed
   B. Redundant work is a function of the die angle
   C. Relative motion between the billet surface and the container wall is always present
   D. Hollow ram is used for indirect extrusion

4. Pick out the wrong statement?

   A. Processing of thermosetting plastics is ideally done by injection moulding
   B. Processing of thermoplastics is ideally done by compression moulding
   C. Mass production of seamless pipes are done by electrical resistance welding (ERW)
   D. Stretch forming is a process of cold drawing

5. Pick out the correct statement about the condensation?

   A. Filmwise condensation gives a lower heat transfer rate than the dropwise condensation
   B. Suitable coating or vapour additive is used to promote film wise condensation
   C. If a condensing liquid does not wet the surface dropwise, even then condensation will take
   place on it
   D. Reynolds number of condensing liquid is based on its mass flow rate

6. Pick out the wrong statement ?

   A. Seam welding, projection welding & spot welding are the classification of electrical resistance
   welding
   B. Electrode tip in spot welding is of copper and the tip diameter should be equal to t (where, t =
   plate thickness to be welded)
   C. In spot welding, two pieces to be joined are overlapped and placed between two electrodes
   D. Mild steel sheet cannot be spot welded

7. Pick out the wrong statement ?

   A. Molecules with symmetrical arrangements (e.g. CH4 or CCl4) are non-polar
   B. Generally, non-polar compounds are chemically inactive, conduct electricity poorly and do
   not ionise
   C. Most of the hydrocarbons are non-polar
   D. None of these

8. Pick out the wrong statement?

   A. Ductile fracture of a stressed material, which exhibits a large plastic deformation is commonly
   caused by the formation and coalescence of voids in the necked region
   B. Brittle fracture is caused by the propagation of pre-existing cracks in the material and involves minimum plastic deformation
   C. Fatigue fracture of a material is always brittle in nature and takes place due to the existence of
   line imperfections
   D. Brittle materials are generally tested in tension

9. Pick out the wrong statement about nucleate boiling ?

   A. Bubble generation is by expansion of entrapped gas/vapour at small cavities in the surface
   B. Surface temperature is greater than the saturation temperature of the liquid
   C. Heat transfer from the surface of the liquid is less than that in film boiling
   D. The temperature is less than that of film boiling

10. Pick out the wrong statement ?

    A. The equivalent stiffness of two springs (of equal stiffness ‘S’) in series is S/2 while in parallel
    is 2S
    B. For a helical spring, deflection is proportional to D3 (D = mean coil diameter) or d4 (d = wire
    diameter)
    C. Crushing load or columns is less than the buckling load
    D. Modulus of resilience is proportional to (stress at elastic limit)2