Building Materials - Section 1 | Multiple Questions and Answers

46.	Plastic

	A.	is an organic substance
	B.	consists of natural or synthetic binders
	C.	finished products are rigid and stable at normal temperature
	D.	is capable of flow when necessary heat and pressure are applied

47.	Vanadium steel is generally used for

	A.	railway switches and crossing
	B.	bearing balls
	C.	magnets
	D.	axles and springs.

48.	Pick up the correct statement from the following:

	A.	In basic Bessemer process, the steel heats the converter
	B.	In open-hearth process, the furnace heats the steel
	C.	In Siemens process, the impurities of pig iron are oxidised by the oxygen of the ore
	D.	all the above.

49.	The process of manufacturing steel by heating short lengths of wrought iron bars mixed with charcoal in fire clay crucibles and collecting the molten iron into moulds, is known as

	A.	Cementation process
	B.	Crucible process
	C.	Bessemer process
	D.	Open hearth process.