Plaster of Paris is obtained by calcining
Bauxite
Gypsum
Lime stone
None of these
Correct Answer :
B. Gypsum
Related Questions
Plastic bitumen is generally used for
Road pavements
Expansion joints
Crack fillings
None to these
Formula for quick lime, is
CaCO3
Ca(OH)2
CO3CO2
None to these
The commonly used drying oil for oil paints, is
Olive oil
Linseed oil
Kerosene oil
Acetate of lead
The most commonly used synthetic abrasive is
Aluminium carbide
Boric acid
Silicon
All of these
Stainless steel resists corrosion due to
Carbon
Sulphur
Vanadium
Chromium
Asbestos
Is an excellent insulator for heat and electricity
Is fire-proof and acid proof
Has sp. gravity equal to 3.10
All the above
The weight of a good quality brick when immersed in water for a period of 16 hours should not exceed the weight of dry brick
20 %
15 %
10 %
None of these
Lime mortar is generally made with
Quick lime
Fat lime
Hydraulic lime
Plain lime
Seasoning of timber is done
To make it water proof
To paint its surface
To increase its temperature
To remove water
The most important constituent of varnish, is
Drier
Solvent
Resin
All the above
Mastic asphalt is
Water proof
Fire proof
Elastic
All the above
Stones used for rubble masonry must be
Soft
Hard
Light
Heavy
Polymerization helps to improve the property of
Strength
Rigidity
Elasticity
All of these
Pick up the correct statement from the following: Method of sawing timber
Tangentially to annual rings, is known as tangential method
In four quarters such that each board cuts annual rings at angles not less than 45°, is known as quarter sawing method
Cut out of quarter logs, parallel to the medullary rays and perpendicular to annual rings, is known as radial sawing
All the above
A rock contains only one mineral. It is called
Homogeneous
Non-homogeneous
Monomineralic
Polymineralic
The percentage of alumina and silica in good fire clay vary respectively is
25, 75
30, 70
35, 65
All of these
Index number expressing the relative sizes of both coarse and fine aggregates, is called
Proportioning of aggregates
Fineness modulus
Grading of aggregates
None of these
The most durable varnish is
Water varnish
Spirit varnish
Turpentine varnish
Oil varnish
Plastic
Is an organic substance
Consists of natural or synthetic binders
Finished products are rigid and stable at normal temperature
All the above
The weight of 1 m3 of brick earth, is about
1200 kg
1500 kg
1800 kg
2000 kg
Basalt is
Sedimentary rock
Metamorphic rock
Extrusive igneous rock
Intrusive igneous rock
Bitumen emulsion is
A liquid containing bitumen in suspension
A paint
Used as anti-corrosive paint
All the above
Knots in timber are
Defects caused by crushing fibres
Splits radiating from the centre
Speckled strains
Signs of branches cut off
Priming consists of
One part of white lead, 8 parts of chalk and four parts of twice boiled linseed oil
8 parts of white lead, one part of chalk and four parts of twice boiled linseed oil
One part of white lead, 8 parts of chalk and one part of linseed oil
None to these
The method of addition polymerization is used for obtaining:
Polystyrene
Polypropylene
Polyvinylchloride
All of these
The internal size of mould used in brick preparation is
Equal to the size of a fully burnt brick
Smaller than the size of a fully burnt brick
Greater than the size of a fully burnt brick
None of the above
Second class bricks
Are of dark brown colour
Produce a metallic sound when struck
Are well burnt
Are under burnt
The nominal size of the modular brick is
190 mm × 90 mm × 80 mm
190 mm × 190 mm × 90 mm
200 mm × 100 mm × 100 mm
200 mm × 200 mm × 100 mm
The rocks in which argil (or clay) predominates, are called
Siliceous rocks
Argillaceous rocks
Calcareous rocks
Igneous rocks
Pick up the non-inflammable plastic from the following:
Cellulose acetate plastics
Polyvinyl chloride plastics
Phenol formaldehyde plastic
Urea formaldehyde plastic