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
Correct Answer :
D. All the above
Related Questions
The pressure acting on the stones in stone masonry construction should be
Along the direction of bedding planes
At 45° to the direction of bedding planes
At 60° to the direction of bedding planes
Perpendicular to the direction of bedding planes
Study the following statements. (i) Hydraulic lime is suitable for white washing, (ii) Fat lime is suitable for whitewashing, (iii) Hydraulic lime is suitable for making mortar, (iv) Fat lime is suitable for making mortar. The correct answer is
(i) and (iv)
(ii) and (iii)
(i) and (ii)
(iii) and (iv)
The material generally not used as extender in paints, is
Powdered silica
Gypsum
Talc
Zinc white
Porcelain is used as:
Sanitary wares
Electric insulators
Storage vessels
Reactor chambers
Minimum required water cement ratio for a workable concrete, is
0.30
0.40
0.50
0.60
Fibre boards can be
Distempered
Painted
Painted and distempered
Used for furniture
The stretcher bond in brick masonry can be used only when the thickness of wall is
90 mm
180 mm
190 mm
280 mm
Proper amount of entrained air in concrete results in (i) Better workability (ii) Better resistance to freezing and thawing (iii) Lesser workability (iv) Less resistance to freezing and thawing The correct answer is
(i) and (ii)
(i) and (iv)
(ii) and (iii)
(iii) and (iv)
A well seasoned timber may contain moisture up to
4 to 6 %
6 to 8 %
8 to 10 %
10 to 12 %
The constituent of cement which is responsible for all the undesirable properties of cement is
Di-calcium silicate
Tri-calcium silicate
Tri-calcium aluminate
Tetra calcium alumino ferrite
A bull nose brick is not used for
Rounding off sharp corners
Pillars
Decoration purpose
Arches
A 1st class brick immersed in water for 24 hours, should not absorb water (by weight) more than
10 %
15 %
20 %
25 %
The stone suitable for rubble masonry should be.
Hard
Tough
Heavy
Light
Percentage of carbon content in mild steel is
Less than 0.25
Between 0.25 and 0.7
Between 0.7 and 1.5
Greater than 1.5
A rock contains only one mineral. It is called
Homogeneous
Non-homogeneous
Monomineralic
Polymineralic
The most commonly used retarder in cement is
Gypsum
Calcium chloride
Calcium carbonate
None of the above
Rapid hardening cement contains
Tri-calcium silicate
Tri-calcium aluminate
Tetra-calcium alumino-ferrite
Di-calcium silicate
Pug mill is used for
Preparation of clay
Moulding of clay
Drying of bricks
Burning of bricks
Pick up the compound responsible for early strength of cement from the following:
Tetra-calcium alumino-ferrite
Tri-calcium silicate
Tri-calcium aluminate
Di-calcium silicate
The most commonly used base for timber painting, is
Red lead
Zinc white
White lead
Titanium white
Pick up the correct statement from the following:
The plywoods do not split or crack due to changes in atmosphere
The commercial plywoods are available upto 150 cm wide and upto 300 cm long
The plywoods possess uniform tensile strength in all directions
All the above
Steel contains carbon approximately
1.50% to 5.6%
0.05% to 1.75%
0.25 %
None to these
Stainless steel resists corrosion due to
Carbon
Sulphur
Vanadium
Chromium
Plywood is made from
Common timber
Bamboo fibre
Teak wood only
Asbestos sheets
Commonly used thinner in
Lacquer paints, is alcohol
Cellulose paints is ethyl acetate
Oil paints, is naphtha
All the above
For construction of structures under water, the type of lime used, is
Hydraulic lime
Fat lime
Quick lime
Pure lime
Quick lime is (i) Slow in setting (ii) Rapid in slacking (iii) Good in strength The correct answer is
Only (i)
Only (ii)
Both (i) and (ii)
Both (ii) and (iii)
The main constituent of fly-ash, is
Aluminium oxide
Silica
Ferrous oxide
All of these
Shingle is
Decomposed laterite
Crushed granite
Water bound pebbles
Air weathered rock
Brass is an alloy of
Copper and zinc
Zinc and lead
Tin and silver
Zinc and nickel