Dryness fraction of dry steam is
0
∞
1
0.5
Correct Answer :
C. 1
Related Questions
Basic open hearth furnace (BOF) is not used for producing __________ steel.
Killed
Rimming
High alloy
None of these
Boiler draught of 10 mm water column is equivalent to
1 kgf/m2
10 kgf/m2
10 kgf/mm2
1 kgf/mm2
The surface tension of a liquid, at critical temperature is
Indeterminate
Zero
Infinity
Same as that at any other temperature
Which of the following is not a principal alloying element for the structural steel?
Molybdenum
Nickel
Manganese
Chromium
If a solid is compressed adiabatically in its elastic range, its __________ remains constant
Internal energy
Enthalpy
Entropy
Temperature
The main reducing agent in iron blast furnace is
Carbon dioxide
Carbon monoxide
Oxygen
Air
Air intake for an air compressor should be preferably taken from
A site, where cooling towers are located nearby
A site, where open coal yard in located nearby
An air conditioned room maintained at a temperature of 18°C
An outside atmosphere at 10°C
The efficiency of a Carnot heat engine operating between absolute temperatures T1 and T2 (when, T1 > T2) is given by (T1 - T2)/T1. The co-efficient of performance (CO.P.) of a Carnot heat pump operating between T1 and T2 is given by
T1/(T1-T2)
T2/(T1-T2)
T1/T2
T2/T1
Consumable electrodes are used in the __________ welding.
Gas
Arc
Thermit
Resistance
Blow off cock is provided in steam boiler to
Guard the boiler in case of abnormal rise in steam pressure
Drain out water and sludge during its repair
Regulate the supply of water in boiler
Put out the fire in the furnace when the water level in the boiler falls to unsafe limit
For a spontaneous natural process at constant temperature and pressure, the free energy of the system always
Increases
Decreases
Remain constant
Increases to a maximum before decreasing
A gas which is collected over water becomes moistened due to water vapor, exerts its own partial pressure at the gas temperature, which is termed as its
Aqueous tension
Saturated humidity
Vapor pressure
Absolute humidity
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
Transition from laminar to turbulent zone in free convection heat transfer is governed by the critical value of
Grashoff number
Grashoff number & Reynolds number
Reynolds number
Grashoff number & Prandtl number
Thermistors are used in __________ devices.
Voltage measuring
Temperature measuring
Temperature compensating
Both (B) & (C)
In a good rimming steel
Carbon and silicon should be low
Silicon should be low but carbon should be high
Both silicon & carbon should be high
Silicon should be high but carbon should be low
What is the critical radius of insulation (cms) for a metallic cylinder, if the convective heat transfer co-efficient with the ambient atmosphere is 5 W/m2. °K? Thermal conductivity of metal and insulation material are 40 and 0.1 W/m.°K respectively.
2
8
10
40
__________ is the process used for setting up compressive stresses in the surface of a metal to improve its fatigue strength.
Lancing
Shot peening
Slugging
Spinning
What is the pH of distilled water?
0
1
7
14
Lead is poured into the joint between two __________ pipes.
Mild steel
Concrete
Cast iron
Asbestos cement
The hardenability of steel decreases with
Decrease in dislocation density
Increase in solutionising temperature
Increase in strength
Decrease in grain size
Most important property of steels for use in automobile bodies is the
Formability
Yield strength
Toughness
Resilience
Stresses encountered in the metal forming processes are less than the __________ of the material.
Fracture strength
Yield strength
Elastic limit
Limit of proportionality
Cemented carbide tools are not suitable for cutting
Aluminium
Brass
Cast iron
Steel
If the demand for an item is trebled and the order cost is reduced to one third, then the economic order quantity
Is trebled
Remains unchanged
Decreases by a factor of 3
Decreases by a factor of 1/3
Maximum heat dissipation occurs from a steel wire (k = 0.5 W/m. k) of 15 mm diameter exposed to air (h = 20W/m2 .k), when the insulation thickness is __________ mm.
15
25
10
30
Out of the following, the alloy which has equal percentage of constituents, is
White metal
Gun metal
Duralumin
Constantan
Square steel key is normally strong in failure by shear & crushing. Keys are normally made of __________ steel bars.
Hot rolled mild
Cold rolled mild
Forged
Machinable stainless
__________ the exhaust gas is an indication of the incomplete combustion of fuel.
Low temperature of
High temperature of
High % of CO in
High % of CO2 in
Particle nature of cathode rays is proved due to the fact that they
Travel in a straight line
Get deflected by magnetic electric field
Produce fluorescence
Heat the exposed material