481. Addition of nickel to copper improves its
Machinability
Ductility
Strength
Hardness
✅ The correct answer is option D.
Materials and Construction MCQs
482. White cast iron as compared to grey cast iron is
More durable
Very brittle
Very hard
All of the above
✅ The correct answer is option D.
483. A bearing metal should not have
Enough plasticity
Low thermal conductivity
Low co-efficient of friction
High toughness
✅ The correct answer is option B.
485. Tubes of multiple effect evaporator used for concentration of sugar cane juice are made of
Nickel
Copper
Stainless steel
Brass
✅ The correct answer is option B.
486. Which of the following has the least carbon percentage?
Low carbon steel
Mild steel
Wrought iron
White cast iron
✅ The correct answer is option C.
487. Babbit metal (used for making bearings) comprises of
Mainly tin (85%) and lead
Saw dust and iron dust mixture
Zinc and aluminium
Copper and aluminium
✅ The correct answer is option A.
488. For handling sulphuric acid of 95% strength, the suitable material of construction for pipes is
Stainless steel
Cast iron
Aluminium
Nickel
✅ The correct answer is option B.
489. __________ is a donor impurity for semi-conductors.
Boron
Antimony
Gallium
None of these
✅ The correct answer is option B.
490. Gas holder of a gobar (cowdung) gas plant is made of
Molybdenum stainless steel
Tin
Mild steel
Aluminium
✅ The correct answer is option C.