273. Mild steel contains carbon upto
a ) 0.10 %
b ) 0.20 %
c ) 0.25 %
d ) 0.30 %
274. The unit weight of steel in taken as
a ) 7.2 ton / m³
b ) 7.4 ton / m
c ) 7.6 ton / m³
d ) 7.8 ton / m³
275. Vanadium steel in generally used for
a ) railway switches and crossing
b ) bearing balls
c ) magnets
d ) axles and springs
276. Cast iron is used for
a ) structural works in beams
b ) small size water pipes
c ) columns and struts
d ) none of the above
277. Mild steel is used for
a ) structural works in beams
b) Small size water pipe
c) Columns and struts
d) none of the above
278. Wrought iron is used for
a ) structural works in beams
b ) small size water pipes
c ) columns and struts
d ) none of the above
279. The types of steel used for precision leveling staff in
a ) titanium steel
b ) carbon steel
c ) invar
d ) stainless steel
280 The steel used for rails under heavy traffic and sharp curves in
a ) nickel steel
b ) chrome steel
c ) manganese steel
d ) vanadium steel of rails in
281. The steel used for manufacture of rails in
a ) bessemer steel
b ) mild steel
c ) cast steel
d ) stainless steel
282. Softer variety of steel may be obtained by
a ) cementation process
b ) crucible process
c ) bessemer process
d ) open hearth process
283. Brass is an alloy of
a ) copper and zinc
b ) zinc and lead
c ) lead and silver
d ) none of the above
284. Bronze is as alloy of
a ) copper and tin
b ) tin and zinc
c ) zinc and lead
d) lead and silver
285. Invar is an alloy of
a ) copper and nickel
b ) nickel and steel
c ) steel and zinc
d ) zinc and lead
286. Solder is an alloy of
a ) nick el and steel
b ) steel and lead
c ) lead and tin
d ) tin and zinc
287. German silver is an alloy of
a ) zinc , lead and nickel
b ) silver , gold and lead
c ) copper , nickel and zinc
d ) all of the above
288. Monel metal is an alloy of
a ) nickel and copper
b ) copper and zinc
c ) zine and tin
d ) tin and lead
289 , Stainless steel resists corrosion due to
a ) carbon
b ) chromium
c ) sulphur
d ) vanadium
290. For the manufacture of stainless steel , steel is mixed width
a ) chromium
b ) nickel
c ) tungsten
d ) none of the above
291. Galvanizing means
a ) depositing a fine film of zinc on iron / steel by dipping it in molten zinc
b ) depositing a fine film of tin on iron / steel by dipping it in molten tin
c ) depositing a fine film of nickel on iron / steel by dipping it in molten nickel
d ) all of the above
292. A combination of metals with other substances is called
a ) alloy
b ) pig iron
c ) wrought iron
d ) cast iron
293 . The main purpose of manufacture of alloys steel is to attain a certain properties like
a ) strength
b ) hardness
c ) toughness
d ) all of the above
294. The artificial seasoning of timber may
a ) reduce moisture
b ) make light and strong
c ) remove moisture
d ) make fire resistance
295. Which one of the following does not belong to endogenous trees ?
a ) palm
b ) bamboo
c ) teak
d ) cane
296. Which one of the following does not belong to exogenous trees ?
a ) coconut
b ) teak
c ) sisham
d ) sal
297. The solution of salts from the soil absorbed by the trees which becomes a viscous solution due to loss of moisture and action of carbon dioxide is known as
a ) pith
b ) cambium
c ) bark
d ) sap
298. The age of tree can be judged from
a ) the height
b ) the diameter
c ) annual rings
d ) piths
299. The no . of the annual ring in a log of 30 then the life of the timber is
a ) 20 year
b ) 25 year
c ) 30 year
d ) 35 year
300. The layer between the bark of the tree and the sapwood which is not yet converted into wood is called
a ) heartwood
b ) cambium layer
c ) softwood layer
d ) pith