Thermal conductivity of a material does not depend upon its_____________________?

Question: Case hardening of a material is
[A].

followed by tempering or carburising.

[B].

preceded by its tempering.

[C].

done to get a soft ductile interior with a very hard surface.

[D].

carried out to get extreme hardness in its core.

Answer: Option D

Explanation:

No answer description available for this question.

Question: A reduction in thermal resistance during heat transfer does not occur in the
[A].

convection heat transfer by stirring the fluid and cleaning the heating surface.

[B].

conduction heat transfer by reduction in the material thickness and increase in the thermal conductivity.

[C].

radiation heat transfer by increasing the temperature and reducing the emis-sivity.

[D].

none of these.

Answer: Option C

Explanation:

No answer description available for this question.

Question: In the commercial production of which of the following metals, matallothermic reduction is used ?
[A].

Copper

[B].

Zinc

[C].

Zirconium

[D].

Nickel

Answer: Option B

Explanation:

No answer description available for this question.