CHEMICAL ENGINEERING

Question: Brinell hardness number (BHN) of a material is a number, which has
[A].

no dimension.

[B].

unit of length.

[C].

unity of force/area.

[D].

unit of force/length.

Answer: Option C

Explanation:

No answer description available for this question.

Question: __________ of test specimens is not involved in any hardness testing method.
[A].

Fracture

[B].

Indentation

[C].

Wear

[D].

Scratch

Answer: Option A

Explanation:

No answer description available for this question.

Question: __________ rubber is generally used for making ‘O’ rings used for vacuum sealings.
[A].

Natural

[B].

Neoprene

[C].

Butadiene

[D].

Nitrile

Answer: Option B

Explanation:

No answer description available for this question.

Question: A form of stress corrosion failure termed as ‘season cracking’ is generally observed in
[A].

thermosetting polymers.

[B].

high carbon steels.

[C].

brasses.

[D].

borosilicate glasses.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Magnetic permeability of iron is increased by its
[A].

decarburising.

[B].

alloying with cobalt.

[C].

purification.

[D].

alternate heating & cooling.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Dislocations are __________ defects.
[A].

point

[B].

line

[C].

volume

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: Maximum change in the hardness of mar tensite occurs in the carbon content range of __________ percent in steel.
[A].

0.01 to 0.10

[B].

0.2 to 0.4

[C].

0.5 to 0.7

[D].

0.8 to 1.0

Answer: Option B

Explanation:

No answer description available for this question.

Question: Nickel and __________ are the alloying element added in steel to increase its toughness.
[A].

molybdenum

[B].

chromium

[C].

vanadium

[D].

silicon

Answer: Option D

Explanation:

No answer description available for this question.

Question: With increasing carbon percent in steel beyond 0.8%, its ultimate tensile strength (UTS) and __________ is not affected.
[A].

impact strength

[B].

percent elongation

[C].

hardness

[D].

both ‘b’ & ‘c’

Answer: Option A

Explanation:

No answer description available for this question.

Question: Change in volume of metals from absolute zero temperature to their melting points is
[A].

almost same for all metals.

[B].

different for different metals.

[C].

less for low melting point metals.

[D].

less for high melting point metals.

Answer: Option A

Explanation:

No answer description available for this question.