Secondary hardening in steels arises out of the _____________________?
(A) Precipitation of fine alloy carbides at high temperatures
(B) Refinement of ferrite grain size by working
(C) Decomposition of retained austenite upon heat treatment
(D) Precipitation of complex inter-metallic upon heat treatment
____________________ joint is mostly used for joining pipes carrying water at low pressure ?
(A) Nipple
(B) Socket
(C) Union
(D) Bell and spigot
Silicon percentage in the silicon steel used for electrical appliances/equipments is_________________?
(A) 0.3-0.4
(B) 12-14
(C) 3-4
(D) 20-25
Catalyst used in the ‘catalytic converter’ employed in automobile exhaust line for complete combustion/oxidation of carbon monoxide, nitrogen oxides and hydrocarbons is__________________?
(A) Alumina
(B) Platinum
(C) Vanadium pentoxide
(D) Iron oxide
Annealing of cast iron__________________?
(A) Softens it to facilitate machining
(B) Decreases the free carbon
(C) Increases the strength
(D) None of these
Thermistors are used in _____________ devices?
(A) Voltage measuring
(B) Temperature measuring
(C) Temperature compensating
(D) Both
The dew point of moist air becomes ____________________ with decrease in its relative humidity ?
(A) Less than the wet bulb temperature
(B) More than the wet bulb temperature
(C) More than the dry bulb temperature
(D) Equal to wet bulb temperature
Basicity [%Cao + %MgO + %SiO2) of the slag in Indian blast furnace is in the range of___________________?
(A) 0.7-1.0
(B) 1.1-1.4
(C) 1.5 – 1.8
(D) 2.0 – 2.5
The most commonly used moderator in nuclear power plants is__________________?
(A) Graphite
(B) Light water
(C) Heavy water
(D) Beryllium
Eutectic reaction for iron-carbon system occurs at a temperature of _______________ °C ?
(A) 723
(B) 959
(C) 1147
(D) 1493