An atom bomb works on the principle of
Nuclear fission
Nuclear fusion
Both the nuclear fission & fusion
Ionisation
Correct Answer :
A. Nuclear fission
Related Questions
The following thermocouple may be used for measuring temperature upto 1873°K.
Chromel-alumel
Copper-constantan
Platinum-platinum rhodium
Iron-constantan
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
Temperature profile along the length of a gasgas counter flow heat exchanger is correctly represented by
In an eutectic system, two elements are completely
Soluble in solid state
Insoluble in liquid state
Insoluble in both solid & liquid state
Soluble in liquid state
__________ cannot increase the fatigue strength of a material.
Grain refining
Grain coarsening
Surface hardening
Shot peening
Pick out the wrong statement.
The X-rays cannot be deflected by electric field unlike cathode rays
The intensity of X-rays can be measured by ionisation current produced due to the ionisation of gas by X-rays
The quality of X-rays can be controlled by varying the anode-cathode voltage
Crystal structure of a material can be studied by an electron microscope
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'
Yield strength of a material is determined by the __________ test.
Creep
Tension
Compression
Endurance
Plants produce carbohydrates from the CO2 present in the atmosphere by
Polymerisation
Photochemical reaction
Oxidation
None of these
Potable water means the water used for
Fire-fighting
Cooling
Drinking
Evaporation to produce steam
Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called
Tempering
Hardening
Annealing
Normalising
The minimum temperature to which the water can be cooled in a cooling tower is the __________ temperature of air.
Ambient
Dry bulb
Dew point
Wet bulb
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 bank of tubes located at the back of the domestic refrigerators are the __________ tubes.
Refrigerant cooling
Evaporator
Condenser
Throttling
Dislocation cross-slip is difficult in those materials, which have
Large number of slip systems
High work hardening rate
Coarse grain size
Low stacking fault energy
There are one octahedral void and __________ tetrahedral void in the closest packing of atoms.
One
Two
Three
None of these
Vernier calipers cannot be used to measure the
I.D. & O.D. of the shaft
Thickness of parts
Depth of holes
Clearance between two mating surfaces
Super conduction in metals is observed at a temperature of __________ °K.
<100
>100
About 273
About 373
Window panes of aeroplanes are normally made of
Perspex (PMMA)
Teflon (PTFE)
Bakelite (phenol formaldehyde)
Polystyrene
The best lubricants for a machine working at high temperature & load is
Grease
Solid lubricant
Animal oils
Mineral oils
Wave length of X-rays is about 1 angstrom; however it cannot pass through a sheet of
Paper
Cloth
Lead
Aluminium
Pressure exerted by a liquid depends upon its
Surface tension
Density
Viscosity
Buoyancy
Maximum consumption of limestone is in the __________ industry.
Iron and steel
Cement
Glass
Fertiliser
Which of the following materials does not form adherent oxide film on surface?
Copper
Nickel
Aluminium
Gold & silver
Machinability of hard alloys and tool steels is improved by
Spheroidising
Annealing
Tempering
Normalising
Addition of silicon to cast iron
Promotes graphite module formation
Improves its ductility
Does not promote graphite flakes formation
Increases the fluidity of molten metal
Tesla metre per ampere (T. m/A) is the unit for the measurement of
Magnetic susceptibility
Magnetic moment
Permeability of free space
Flux density
In inventory control theory, the economic order quantity (EOQ) is the
Lot size corresponding to break even analysis
Average level of inventory
Optimum lot size
None of these
Which of the following metals is not subjected to electrolytic refining/purification?
Copper
Zinc
Tin
Aluminium
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)