Asbestos
Is a natural fibrous mineral substance
Is composed of hydrous silicates of calcium and magnesium (CaSiO3, 3MgSiO3)
Contains iron oxide and alumina
All the above
Correct Answer :
D. All the above
Related Questions
In stone masonry, stones (stratified rocks) are so placed that the direction of pressure to the plane of bedding is
Right angles
45°
60°
Parallel
Minimum of 40% of iron, is available in
Magnetite
Red haematite
Limonite
Black band
The steel used for the manufacture of rails, is
Bessemer steel
Mild steel
Cast steel
Stainless steel
Pick up the correct statement from the following:
The low voltage porcelain is prepared by wet process
The high voltage porcelain is prepared by dry process
The low voltage porcelain is prepared by dry process
None of the above
The slump recommended for mass concrete is about
25 mm to 50 mm
50 mm to 100 mm
100 mm to 125 mm
125 mm to 150 mm
The ultimate tensile strength of structural mild steel is about
160 N/mm²
260 N/mm²
420 N/mm²
520 N/mm²
Cast iron contains carbon approximately
1.5% to 5.5%
0.05% to 1.75%
0.250 %
None to these
With increase in moisture content, the bulking of sand
Increases
Decreases
First increases to a certain maximum value and then decreases
First decreases to a certain minimum value and then increases
Pick up the correct statement from the following:
The lime in excess makes the cement unsound and causes the cement to expand and disintegrate
The silica in excess makes the cement stronger but its setting time also increases
The excess amount of alumina weakens the cement
All the above
Pick up the correct statement from the following:
Air bubbles in casting produce a dull sound by tapping their surfaces lightly with a hammer
Cupola furnace is used for the manufacture of cast iron
Red short iron is of no value for welding purpose
All the above
The softest rock is
Marble
Diamond
Talc
Quartz
The compound of Portland cement which contributes to the strength after two to three years is
Tri-calcium silicate
Di-calcium silicate
Tri-calcium aluminate
Tetra-calcium alumino ferrite
Pick up the correct statement from the following:
The substance which consists of one primary chemical, is known as monomer
The polymer consists of thousands of monomers joined together
The polymer molecule is called macro-molecule
All the above
For one cubic metre of brick masonry, number of bricks required, is
400
425
450
500
The stone suitable for rubble masonry should be.
Hard
Tough
Heavy
Light
The practical limit of moisture content achieved in air drying of timber is
5 %
15 %
25 %
35 %
A rock contains only one mineral. It is called
Homogeneous
Non-homogeneous
Monomineralic
Polymineralic
Brittleness of cold is due to an excess of
Sulphur
Carbon
Phosphorus
Silicon
Refractory bricks are used for
Retaining walls
Columns
Piers
Combustion chambers
Spirit varnish generally consists of
Oil, wax and resin
Alcohol, wax and turpentine
Pigment and synthetic resin
Spirit and shellac
Refractory bricks are
Neutral refractory bricks
Acid refractory bricks
Basic refractory bricks
All the above
Pig iron is manufactured from the ores by
Dressing
Calcination and roasting
Smelting
All the above
Putty is
Made with finely powdered chalk and linseed oil
Used for fixing glass panes
Softened by a solution of pearl ash and quick-lime soaked in water
All the above
Which of the following is a mineral?
Basalt
Granite
Quartz
Syenite
Quartzite is a
Metamorphic rock
Argillaceous rock
Calcareous rock
Siliceous rock
Pick up the correct statement from the following:
The theory of formation of concrete is based on the phenomena of formation of voids
The bulking of sand is taken into account while volumetric proportioning of the aggregates
The dry sand and the sand completely flooded with water, have practically the same volume
All the above
The ratio of the thickness of web to that of flange of steel rolled structural beams and channels is
Less than 1
Equal to 1
Greater than 1
Less than 1 in beams but greater than 1 in channels
Sewer pipes are made of
Earthen ware
Stone ware
Refractory clay
All the above
Knots in timber are
Defects caused by crushing fibres
Splits radiating from the centre
Speckled strains
Signs of branches cut off
Stainless steel resists corrosion due to
Carbon
Sulphur
Vanadium
Chromium