Which one of the following materials is very hard and very ductile ?

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Q: 109 (IAS/2000)
Which one of the following materials is very hard and very ductile ?

question_subject: 

Science

question_exam: 

IAS

stats: 

0,25,62,14,36,12,25

keywords: 

{'materials': [0, 1, 1, 0], 'ductile': [0, 1, 0, 0], 'tungsten': [0, 0, 0, 2], 'cast iron': [0, 0, 1, 0], 'carborundum': [0, 0, 0, 1], 'nichrome': [0, 1, 1, 1]}

Explanation:

Option 1: Carborundum is an extremely hard material (9.5 on the Mohs scale of mineral hardness), but it`s not ductile, it`s a compound of silicon and carbon and usually brittle.

Option 2: Tungsten is the metal with the highest melting point and it is hard, but its ductility is low at room temperature. It becomes ductile when heated.

Option 3: Cast iron is a group of iron-carbon alloys with a carbon content greater than 2%. It`s known for its excellent casting properties, but it`s not very hard or ductile.

Option 4: Nichrome is a non-magnetic alloy of nickel, chromium, and often iron. It`s known for its high resistivity and resistance to oxidation. It is both hard and ductile, making it the correct answer in this case.

Remember, a material that is ductile can be drawn out into a wire. Hardness refers to a material`s resistance to permanent deformation.