Which of the following emissions in the exhaust gas of an I.C. engine causes the formation of photochemical smog?
Nitrogen oxides
Hydrocarbons
Both 'a' & 'b'
Carbon monoxide
Correct Answer :
C. Both 'a' & 'b'
Related Questions
Magnetic permeability of iron is increased by its
Decarburising
Alloying with cobalt
Purification
Alternate heating & cooling
Speed of a submarine in deep sea & that of an aeroplane is measured by a/an
Pitot tube
Hot wire anemometer
Rotameter
Stroboscope
Identify the correct statement.
Sphlerite is zinc oxide
The first law of the thermodynamics is stated as δE = δQ - δW
Lead can be produced in a blast furnace
T. ferrooxidans is a fungus that can be used for leaching chalcopyrite
The stress at which extension of the material takes place more rapidly as compared to the increase in load is termed as the __________ point of the material.
Elastic
Ultimate
Yielding
Breaking
The material used for coating the welding electrode is termed as the
Flux
Slag
Protective layer
Binder
Eutectic reaction for iron-carbon system occurs at a temperature of __________ °C.
723
959
1147
1493
Breakeven point represents the condition, when the company runs under no profit no loss condition. In break even analysis, total cost comprises of fixed cost
Only
Plus variable cost
Plus overhead cost
Plus selling expenses
Case hardening is not done by
Nitriding
Hot dipping
Electroplating
Both b & c
A steam pipe is intended to be insulated with two layers of insulating materials of different thermal conductivities. For minimum heat transfer to take place
The better insulation material should be put just next to pipe (i.e., inside)
The better insulating material should be put outside
Either of the insulating material could be put on either side
Steam temperature is considered before deciding as to which insulating material is to be put inside (i.e., just next to the pipe)
Photographic plates are coated with
Silver nitrate
Silver halide
Calcium silicate
Metallic silver
A semi-conductor is damaged & behaves like a conductor, on passing a strong electric current through it, because it heats up the crystals & breaks the covalent bonds resulting in __________ electrons.
Lack of free
Excess of
Decrease in
None of these
Steam condenser tubes are made of admiralty brass, in which percentage of zinc & copper are __________ respectively.
70 & 30
30 & 70
50 & 50
90 & 10
The pressure drop per unit length for laminar flow of fluid through a long pipe is proportional to (where, A = cross-sectional area of the pipe & D = Diameter of the pipe)
A
D
1/A
1/A2
Use of economiser in a boiler plant reduces the fuel consumption for steam generation by about __________ percent.
1
10
30
50
__________ rubber is generally used for making 'O' rings used for vacuum sealings.
Natural
Neoprene
Butadiene
Nitrile
The best lubricants for a machine working at high temperature & load is
Grease
Solid lubricant
Animal oils
Mineral oils
Annealing of white cast iron produces __________ iron.
Grey
Nodular
Malleable
Spheroidal
A material subjected __________ must have high resilience.
Shock loading
Vibration
Fatigue
Tension
Ferromagnetic materials owe their properties to __________ inner sub-shells.
Completely filled
Partially filled
Equally filled
Vacant
Moist climate is the most favourable factor in the site selection far a
Steel plant
Textile factory
Petroleum refinery
Coke oven battery
Calorific value of __________ are almost same.
Lignite & anthracite coal
Lignite & coal gas
Petrol & diesel
Coal gas & natural gas
Age hardening is connected with
Babbitt metal
Gun metal
Stainless steel
Duralumin
Absolute zero pressure can be attained at a temperature of
0°C
50°K
0°R
None of these
For a thermodynamic system undergoing a process, which of the following pairs best expresses the relationship similar to that expressed by the pressure volume plot?
Temperature - entropy
Temperature - pressure
Enthalpy - entropy
Enthalpy-pressure
Reduction in the grain size reduces the __________ of the material.
Fatigue resistance
Tensile strength
Creep resistance
All (A), (B) & (C)
Pick out the wrong statement.
Copper is the metal having the highest electronic conductivity
Hardenability & Weldability of metals are inversely related
Covalent bonding formed by sharing of electrons is present in all semi-conductor materials
Glass transition temperature applies to 'polymers' but not to 'glasses'
In TIG welding, thoriated tungsten electrodes are used, because it
Has higher current carrying capacity
Has better electron emissivity
Is stronger than ordinary tungsten
Is easy to prepare
Out of the following the refractive index is the highest for
Glass
Diamond
Brine
Kerosene
Which of the following test is used for distinguishing among dry oils, semi-drying oils and non drying oils?
Elaiden test
Reichert-Meissl value test
Hunter value test
Iodine value test
Boiling point of water gets lowered at high altitudes (e.g., hills), because
Temperature is low
Atmospheric pressure is low
Atmospheric pressure is high
None of these