For the allotropic forms of iron, the points of arrest are __________________?

Related Mcqs:

1. Points of arrest for iron correspond to__________________?

   A. stages at which allotropic forms change
   B. stages at which further heating does not increase temperature for some time
   C. stages at which properties do not change with increase in temperature
   D. there is nothing like points of arrest
   E. none of the above

2. Which of the following represents the allotropic forms of iron__________________?

   A. alpha iron, beta iron and gamma iron
   B. alpha iron and beta iron
   C. body centred cubic a-iron and face centred cubic a-iron
   D. alpha iron, gamma from and delta iron
   E. none of the above

3. A material is known as allotropic or polymorphic if it __________________?

   A. has a fixed structure under all conditions
   B. exists in several crystal forms at different temperatures
   C. responds to heat treatment
   D. has its atoms distributed in a random pattern
   E. none of the above

4. In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than_______________?

   A. frictional force
   B. viscosity
   C. surface friction
   D. all of the above
   E. none of the above

5. The temperature at which ferromagnetic alpha iron transforms to paramagnetic alpha iron is _______________?

   A. 770°C
   B. 910°C
   C. 1050°C
   D. below recrystallisation temperature
   E. above recrystallization temperature

6. An important property of malleable cast iron in comparison to grey cast iron is the high___________________?

   A. compressive strength
   B. ductility
   C. carbon content
   D. hardness
   E. surface finish

7. Paramagnetic alpha iron changes to gamma iron at_______________?

   A. 770°C
   B. 910°C
   C. 1440°C
   D. 1539°C
   E. none of the above

8. Which of the following is mostly used used as blast furnace fuel for extracting pig iron from iron ores?

   A. Brown coal
   B. Anthracite coal
   C. Hard coke
   D. Woodchar coal

   Submitted by: Faheem Zaman Dhaunroo

9. The percentage of carbon in grey iron castings usually varies between __________________?

   A. 0.5 to 1%
   B. 1 – 2%
   C. 2.5 to 4.5%
   D. 5 – 7%
   E. 7-9%.

10. Principle of similitude forms the basis of_________________?

    A. comparing two identical equipments
    B. designing models so that the result can be converted to prototypes
    C. comparing similarity between design and actual equipment
    D. hydraulic designs
    E. performing acceptance tests