Large diameter reinforced cement concrete (RCC) pipes are generally joined by __________ joint.
Flanged iron
Collar
Flexible
Expansion
Correct Answer :
B. Collar
Related Questions
Photographic plates are coated with
Silver nitrate
Silver halide
Calcium silicate
Metallic silver
Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8
°C
°F
°K
°R
Pick out the wrong statement.
A ferromagnetic material becomes paramagnetic above the 'Curie temperature'
Permanent magnets are made of hard materials, whereas electromagnets require soft magnetic materials
Soft magnetic materials (e.g., pure iron) have higher permeability and low hysterisis loss and coercive forces
Tungsten steel and alnico are not hard magnetic materials
Baffles provided on the shell side of a shell and tube heat exchanger are meant for
Providing support for the tubes
Improving heat transfer
Both 'a' & 'b'
Preventing the fouling of tubes & stagnation of shell side fluid
Routing in production, planning & control is concerned with the
Sequence of operation to be performed
Progress of work performed
Authorisation of work to be performed
Balancing of load on machines
In case of compression of one kg of air, the work done will be the least, when the value of polytropic index 'n' is
1
1.4
1.5
Y = Cp/Cv
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
Corrosion is
A physical phenomenon
A chemical phenomenon
Same as erosion
An uncontrollable phenomenon
For infinite parallel planes having emissivities ε1 & ε2, the interchange factor for radiation from surface 1 to surface 2 is given by
Shrinkage allowance on pattern is provided to compensate for shrinkage when the
Metal changes from liquid state to solid state at freezing temperature
Solid phase temperature drops from freezing temperature to the room temperature
Liquid metal temperature drops from pouring temperature to room temperature
Liquid metal temperature drops from pouring temperature to freezing temperature
Which of the following are considered applications of ultrasonic testing?
Determination of elastic constant
Detection of defects in metal
Measurement of material thickness
None of the above
Which of the following is normally not found in both the S.I. (petrol) & C.I. (diesel) engines?
Air filter
Fuel injector
Exhaust silencer
Battery
With increase in compression ratio, the volumetric efficiency of air compressor
Increases
Decreases
Remain same
May increase or decrease (depends on the suction pressure)
Magnesium is present in
Haemoglobin
Chlorophyll
Hypo solution
None of these
Pick out the wrong statement.
Ductile fracture of a stressed material, which exhibits a large plastic deformation is commonly caused by the formation and coalescence of voids in the necked region
Brittle fracture is caused by the propagation of pre-existing cracks in the material and involves minimum plastic deformation
Fatigue fracture of a material is always brittle in nature and takes place due to the existence of line imperfections
Brittle materials are generally tested in tension
The __________ of a double acting reciprocating pump as compared to the single acting pump will be almost double.
Flow output
Head developed
Overall efficiency
Weight
For a small scale toy factory, the fixed cost per month is Rs. 5000/-. The variable cost per toy is Rs. 20 and sales price is Rs. 30 per toy. The break even production per month will be __________ toys.
250
500
1000
3000
The ability of tool steel to resist softening at high temperatures is termed as __________ hardness.
Red
Extended
Super
Extreme
Increase in the entropy of a system represents the
Degradation of energy
Decrease in system pressure
Increase in the availability of energy
Increase in the temperature
Which of the following represents the correct time-temperature curve when a block of metal is heated above room temperature & then left to cool in the room following Newton's law of cooling in which the rate of temperature drop will go on decreasing with the passage of time.
Fine grained steels have
High brittleness
Higher tendency to distort
High ductility
None of these
Babbitt lining is used on brass/bronze bearings to increase the
Antifriction properties
Compressive strength
Bearing resistance
Wear resistance
Water-tube boiler is the one, in which
Water passes through tubes and flue gases around it
Tube carrying hot flue gases are immersed in a pool of water
Tubes are placed in vertical position
None of these
Name the safety device used to protect the boiler, when the water level falls below a minimum level.
Blow down valve
Blow off cock
Fusible plug
Safety valve
A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre.
0.01
0.1
0.25
0.5
Oxide layer formed on the non-ferrous metal surface after its annealing is
Removed by acid pickling
Hammered into the surface
Removed with coarse emery cloth
Left as such to protect the surface
The excess air required for the combustion of pulverised coal is of the order of about __________ percent.
5
15
30
45
For the irreversible reaction, Ca+ 2C = Ca C2 , Δ H°298 = - 60000 J . mole-1 . If a system initially containing 2 moles of calcium, 3 moles of carbon and 1 mole of calcium carbide is allowed to react to completion, the heat evolved at 298 K will be
30,000 J
60,000 J
90,000 J
2,40,000 J
An ideal material for making cooking vessels should have
High heat capacity
Low heat capacity
High thermal conductivity
Both (B) and (C)
__________ is the hardest oxide and is hence used where high wear resistance at high temperature is required.
Beryllium
Zirconia
Alumina
Magnesia