Test: Plastics, Ceramics & Composite Materials - 3 - Mechanical Engineering MCQ

Which one is not a characteristics of plastics?

Plasticizers are added in plastic to

Whiskers are

The cermets are example of

A continuous and aligned glass fibre-reinforced composite consists of 40 vol% of glass fibres modulus of elasticity 69 GPa and 60 vol% of a polyester resin that, when-hardened, displays a modulus of 3.4 GPa. What is the modulus of elasticity of this composite in the longitudinal direction?

A continuous and aligned glass fibre-reinforced composite consists of 40 vol% of glass fibres having a modulus of elasticity 80 GPa and remaining volume of a polyester resin that, when hardened, displays a modulus of 4 GPa. What is the elastic modulus of composite material when the stress is applied perpendicular to the direction of fibre alignment?

The matrix phase of fibrous composites may be

Which of the following is not an example of laminar composite?

Wood is

Ceramic cutting tools are made of

Silica is

Which one of the following materials is not a composite?

Consider the following statements regarding composite materials:
1. Material is termed as advanced composite if fibres are directionally oriented and continuous.
2. Reinforced fibres glass products are strong and light weight,
3. Concrete is reinforced with steel bars and the bar becomes matrix.
4. Pearlitic steels are composites.
Q. Which of the above statements are true?

Polythene is

Consider the following statements pertaining to composite materials:
1. The mechanical characteristics of a fibre-reinforced composite depend only on the properties of the fibre.
2. Prestressed concrete should be of a high quality with a low shrinkage and a low creep rate.
3. Whiskers are very thin single crystals that have extremely large length-to-diameter ratio.
Q. Which of the above statements are valid?

Slow and progressive deformation of a material with time under constant stress is called creep.This phenomenon is not exhibited at low temperature by

Select the wrong statement:

Viscoelastic behaviour would be exhibited by

Dextrin is

Consider the following statements:
Thermosetting plastics are
1. Formed by addition polymerization
2. Formed by condensation polymerization
3. Softened on heating and hardened on cooling
4. Moulded by heating and cooling
Q. Which of these statements are true?

Teflon is a

Phenol formaldehyde is a

Structure of a polymer is

Polyesters can be defined as the condensation products of

Match List-I (Materia!) with List-II (Typical use) and select the correct answer using the codes given below the isits:
List - I
A. Branched polyethylene
B. Polyester
C. Polyvinyl chloride
D. Linear Polyethylene
List - II
1. Bottles
2. Textile fibres
3. Films forpackaging
4. Transparent Film

Codes:
      A B C D
(a)  3 2 1  4
(b)  2 3 4  1
(c)  2 3 1  4
(d)  3 2 4  1

Match List-I with List-II and select the correct answer using the codes given below the lists:
List-I
A. Neoprene
B. Bakelite
C. Foamed poly-urethane
D. Araidite
List-II
1. Electric switches
2. Adhesive
3. Thermal insulator
4. Oil seal
Codes:
     A B C D
(a) 4 1 2 3
(b) 1 4 2 3
(c) 4 1 3 2
(d) 1 4 3 2

The molecular weight of vinyl chloride is 62.5. Thus the molecular weight of a polyvinyl chloride with a degree of polymerization of 20000 is