Which of the following statement is incorrect about duralumin?
Assertion (A): Linear polymers are rigid at low temperatures but soft andmouldable at elevated temperatures.
Reason (R): Linear polymers are thermo-setting.
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Tin base white metals are used where the bearings are subjected to
Match List I with List II and select the correct answer using the code given below the Lists:
List I List II
(Material) (Application)
A. Fibre reinforced plastics 1. Automobile tyres
B. Acrylics 2. Aircraft
C. Phenolics 3. Lenses
D. Butadiene rubber 4. Electric switch cover
Code: A B C D A B C D
(a) 1 4 3 2 (b) 2 3 4 1
(c) 1 3 4 2 (d) 2 4 3 1
Which material is used for bushes in the bushed-pin type of flexible coupling?
Thermoplastic materials cannot be produced by:
Which one of the following materials is used for car tyres as a standard material?
Consider the following statements:
Polytetrafluoroethene is
1. A thermoplastic material
2. Having high friction coefficient
3. A thermosetting material
4. Having low friction coefficient
5. An electric insulator
6. Non sticking to surfaces
Which of the above statements are correct?
Why are babbit alloys used for bearing material?
Babbit lining is used on brass/bronze bearings to
The molecular weight of vinyl chloride is 62.5. Thus the molecular weight or apolyvinyl chloride with a degree of polymerization of 20000 is
Which one of the following is correct?
Babbitt are used for
Consider the following statements:Fibre Reinforced Plastics are
1. Made of thermosetting resins and glass fibre
2. Made of thermoplastic resins and glass fibre
3. Anisotropic
4. isotropic
Select the correct answer using the codes given below:
Gunmetal, which is used in journal bearings, contains
Which of the following pairs of plastics and their modes of formation are correctly matched?
1. Polythene…………….. Condensation polymerization.
2. Polycarbonate .............Addition polymerisation.
3. Polystyrene………….. .Addition polymerisation.
4. Polyamide …………….Either by addition or by condensation polymerisation.
Select the correct answer using the codes given below:
Match List I (Material) with List II (Typical use) and the correct answer using the codes given below the Lists:
List I List II
A. Branched polyethylene 1. Bottles
B. Polyester 2. Textile fibres
C. Polyvinylidene chloride 3. Films for packaging
D. Linear Polyethylene 4. Transparent film
A B C D A B C D
(a) 2 3 4 1 (b) 3 2 1 4
(c) 2 3 1 4 (d) 3 2 4 1
What is the process by which two or more chemically different monomers are polymerised to form a cross link polymer together with a by-product such as water or ammonia, known as?
Which one of the following possesses the property of non sparking character?
Assertion (A): Addition polymerization is a primary summation of individualmolecules into long chains,
Reason (R): In addition polymerization, the reaction produces a small molecule asby-product.
Consider the following:
Which of the following properties are possessed by plastics?
1. Good resistance to corrosive atmosphere
2. Ease of fabrication into complex shapes.
3. Good resistance to shocks and vibrations.
Select the correct answer using the code given below:
Consider the following statements in respect of fabrication of plastic products:
1. Compression moulding is analogous to hot pressing of powdered metals.
2. Jet moulding is a modification of compression moulding.
3. Injection moulding is analogous to die casting of metals
4. Transfer moulding is similar to hydraulic extrusion.
Which of these statements are correct?
To reduce the consumption of synthetic resins, the ingredient added is
Consider the following statements:
1. Thermoplastics possess a strong intermolecular bonding compared to that ofthermosetting plastics.
2. Plastics have a high creep under continuous loading.
3. Embrittlement occurs in plastics at low temperature.
Which of these statements are correct?
Which of the following processes can be used for mass production of plasticcontainers (with lid) of 5 liter capacity?
1. Injection moulding
2. Jolt moulding
3. Blow moulding
Select the correct answer using the codes given below:
Codes:
Which one of the following are the processes for thermosetting materials?
1. Compression
2. Transfer moulding
3. Injection moulding
4. Extrusion
Select the correct answer using the codes given below:
Which one of the following statements is not correct?
Match List-I with List-II and select the correct answer using the code given below the Lists:
List-I List-II
(Article) (Processing Method)
A. Disposable coffee cups 1. Rotomoulding
B. Large water tanks 2. Expandable bead moulding
C. Plastic sheets 3. Thermoforming
D. Cushion pads 4. Blow moulding
5. Calendering
Code: A B C D A B C D
(a) 3 5 1 2 (b) 4 5 1 2
(c) 4 3 2 1 (d) 3 1 5 2
Match List I (Type of moulding) List II (Mechanism involved) and select the collect answer using the codes given below the Lists:
List I List II
A. Compression moulding 1. Mould cavity must be heated to cure the plastic forced into it.
B. Injected moulding 2. Similar to Hydraulic extrusion
C. Jet moulding 3. Analogous to the hot pressing of powered metals
D. Extrusion moulding 4. Analogous to die casting of metals
A B C D A B C D
(a) 2 4 1 3 (b) 3 1 4 2
(c) 2 1 4 3 (d) 3 4 1 2
29 docs|220 tests
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29 docs|220 tests
|