Tag: garbage in, garbage out
Questions Related to garbage in, garbage out
Plastic is a polymer consisting of:
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synthetic monomers
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semi-synthetic monomers
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natural monomers
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both a and b
Plastic is a material consisting of synthetic or semi-synthetic organics that can be moulded into solid objects of diverse shapes. Plastics are typically organic polymers of high molecular mass, but they often contain other substances. They are usually synthetic, most commonly derived from petrochemicals, but many are partially natural.
Which plastic is called a fire proof plastic?
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Melamine
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Bakelite
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Teflon
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Acrylic
Melamine is poor conductor of heat and resists fire. Most of the synthetic fibres are poor conductors of heat and electricity. However, melamine is used as a coating on the uniforms of firemen as they are flame resistant.
Which of the following statement is true about thermosetting plastic?
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It undergoes irreversible change during curing
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It can melt and take shape only once
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It cannot be recycled
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All of above
Thermosetting plastics contain polymers that cross-link together during the curing process to form an irreversible chemical bond. It can't be recycled. The cross-linking process eliminates the risk of the product remelting when heat is applied, making thermosetting ideal for high-heat applications such as electronics and appliances.
Why is plastic used in covering of electrical appliances?
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Good conductors of heat and electricity
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Durable
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Poor conductors of heat and electricity
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None of above
Plastic is a poor conductor of heat and electricity.
Plastic can be used as :
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insulator
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conductor
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Both A and B
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None of above
Most plastics are both thermal and electrical insulators, meaning they show high resistance to electrical current and are poor conductors of heat.
Handles of most pans are made up of:
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thermoplastic
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thermosetting plastic
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acrylic
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hemp
Handles of most pans are made up of thermosetting plastic. Thermosetting plastic does not melt easily. These plastic cannot be reshaped again and again.
The world's first fully synthetic plastic was:
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Polystyrene
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Nylon
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Bakelite
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Teflon
The world's first fully synthetic plastic was bakelite, invented in New York in 1907 by Leo Baekeland who coined the term 'plastics'. Bakelite is made from carbolic acid (phenol) and formaldehyde and is referred to as a phenolic resin. Bakelite was the first thermosetting plastic.
Which of the following are the advantages of plastic over metals?
1. Plastics are lighter.
2. Plastics are usually cheaper.
3. Plastics are inert to both acids and alkalis.
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(1) and (2) only
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(1) and (3) only
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(2) and (3) only
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(1) ,(2) and (3)
Nylon is obtained by:
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treating wood pulp
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solidifying water
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mixing coal, air and water
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mixing chemicals
Nylon was first commercially synthesized fibre. The production of nylon was started almost simultaneously in New York and London, thus it got its name (NY for New York and Lon for London) as nylon. Nylon is synthesized from coal, water and air. Fibre of nylon is very strong and it also resembles silk.
Bakelite is an example of ___.
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elastomer
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fibre
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thermoplastic
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thermosetting polymer
A thermosetting plastic, also known as a thermoset, is a polymer material that irreversibly cures. The cure may be induced by heat, generally above $200^o C$ $(392\ F)$, through a chemical reaction or a suitable irradiation.
$Bakelite$ is one example of this type.