Iron ore may contain
Carbon
Silicon
Phosphorus and manganese
All the above
Correct Answer :
D. All the above
Related Questions
The softest rock is
Marble
Diamond
Talc
Quartz
The cracks caused by shrinkage of the exterior surface of the wood exposed to atmosphere, are called:
Radial shakes
Heart shakes
Wind cracks
Twisted fibres
Quartzite, a metamorphic stone is
Hard
Brittle
Crystalline
All the above
Early attainment of strength in rapid hardening cement is mainly due to
Gypsum
Finer grinding
Tri-calcium silicate
Tri-calcium aluminate
Seasoning is
A process of removing sap
Creosoting
Painting with sodium silicate
Coating with tar
Good quality sand is never obtained from
River
Lake
Sea
Gravel powder
The main function of alumina in brick earth is
To impart plasticity
To make the brick durable
To prevent shrinkage
To make the brick impermeable
As per IS specifications, the maximum final setting time for ordinary Portland cement should be
30 minutes
1 hour
6 hours
10 hours
Soundness test of cement determines
Quality of free lime
Ultimate strength
Durability
Initial setting
Refractory bricks are
Neutral refractory bricks
Acid refractory bricks
Basic refractory bricks
All the above
The practical limit of moisture content achieved in air drying of timber is
5 %
15 %
25 %
35 %
To retard the initial setting time of cement, the compound responsible, is
Tri-calcium silicate
Gypsum
Di-calcium silicate
Tri-calcium aluminate
Which of the following ingredients of the brick earth enables the brick to retain its shape?
Alumina
Silica
Iron
Magnesia
In the method of condensation polymerization,
Low-molecular substances are removed from the high molecular substance
The reaction proceeds with an evolution of ammonia
The reaction proceeds with an evolution of hydrogen chloride
All of the above
Pick up the hypabyssal rock from the following:
Granite
Dolerite
Basalt
All the above
Rocks formed due to alteration of original structure due to heat and excessive pressure are called
Sedimentary rocks
Igneous rocks
Metamorphic rocks
None of these
The main ingredient of a good quality brick earth, is
Magnesia
Lime
Silica
Alumina
The steel used in R.C.C. work is
Stainless steel
Mild steel
High carbon steel
Wrought iron
Gypsum consists of
H₂S and CO₂
CaSO4 and H₂O
Lime and H₂O
CO₂ and calcium
Cement paints usually
Contain hydrated lime
Contain 5% to 10% colour pigments
Contain 5% sodium chloride
All the above
The ultimate tensile strength of structural mild steel is about
160 N/mm²
260 N/mm²
420 N/mm²
520 N/mm²
Pick up the correct statement from the following:
Rust is due to formation of oxides
Cast iron oxidises less
Steel oxidises most
All the above
Soundness of cement is tested by
Vicat's apparatus
Le-chatelier apparatus
Compressive strength testing apparatus
None of these
The type of steel used for precision levelling staff, is
Titanium steel
Carbon steel
Invar
Stainless steel
A stone is rejected if it absorbs water more than
5 %
10 %
15 %
20 %
For the manufacture of stainless steel, steel is mixed with
Chromium
Nickel
Tungsten
None of these
The normal consistency of ordinary Portland cement is about
10 %
20 %
30 %
40 %
Which of the following bricks are used for lining of furnaces?
Over-burnt bricks
Under-burnt bricks
Refractory bricks
First class bricks
Pick up the most favourable condition for the rapid growth of fungus for dry rot from the following:
Absence of sun light
Dampness
Presence of sap
All the above
Wrought iron contains carbon upto
0.25 %
1.0 %
1.5 %
2 %