At 100% relative humidity, the dew point temperature of moist air is
Less than the wet bulb temperature
More than the wet bulb temperature
Equal to the wet bulb temperature
Equal to the ambient temperature
Correct Answer :
B. More than the wet bulb temperature
Related Questions
Chlorine acts as a bleaching agent only in the presence of
Dry air
Pure oxygen
Moisture
Sunlight
Which of the following materials does not form adherent oxide film on surface?
Copper
Nickel
Aluminium
Gold & silver
During sensible cooling of air, its wet bulb temperature
Decreases but dew point remains constant
Increases but dew point remains constant
Increases & the dew point decreases
Decreases & the dew point increases
As the fluid flow rate increases, the float of the Rotameter
Rises in the tube
Rotates at higher speed
Rotates at lower speed
Drops down in the tube
A material is capable of resisting softening at high temperature, because of its property termed as
Hot temper
Hot hardness
Fatigue
Creep
Which of the following materials has the least scrap value?
Aluminium
Stainless steel
Brass
Copper
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
Which of the following is the most suitable abrasive for grinding high tensile strength materials?
Silicon carbide
Corundum
Aluminium oxide
Boron carbide
The 'transition temperature' for ductile to brittle behaviour of steel increases with increase in the __________ content in steel.
Carbon
Manganese
Both 'a' nor 'b'
Neither 'a' nor 'b'
Carbon is present in the form of __________ in grey cast iron.
Spheroids
Nodular aggregates of graphite
Flakes
Cementite
For the Stoke's law to be valid in the case of a falling sphere in a fluid, the
Reynolds number (based on sphere diameter) should be < 1
Flow around the sphere should be in turbulent region
Sphere must be metallic
Fluid density should be constant
__________ are normally subjected to sub-zero treatment.
Highly stressed parts
Gauges or precision parts
Cold rolled sheets
Non machinable materials
Alcohols are not suitable as diesel engine fuel because the cetane number of alcohols is
Very low which prevents their ignition by compression
Very high which prevents their ignition by compression
Zero
None of these
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
Steel is welded using the __________ flame.
Carburising
Neutral
Oxidising
All (A), (B) & (C)
__________ 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
__________ joint is usually used for joining cast iron pipes mostly used for temporary pipelines, where it may be necessary to dismantle & reassemble the pipeline very frequently.
Collar
Flanged
Bell and Spigot
Expansion
The value of 
for air & most common gases can be safely assumed to be
0.8
1
1.4
1.8
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
__________ of austenite decreases the hardenability in steel.
Fine grains
Coarse grains
Homogeneity
Dissolved elements (except cobalt)
Production of a hollow product by inflation of a tube or parison is called the __________ process.
Blow moulding
Calendaring
Extrusion
Injection
Coating provided on the electrodes used in the arc welding is not expected to
Add alloying elements
Prevent electrode from contamination
Stabilise the arc
Provide protective atmosphere to weld
In Newton's law of viscosity, which states that the shear stress is proportional to the __________ Co-efficient of viscosity is called dynamic or absolute viscosity(where, V = velocity, 
= velocity gradient).
Angular displacement can be measured suitably by a
Shaft encoder
Linear variable differential transducer (LVDT)
Stroboscope
Tachometer
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
Which of the following is not a characteristic observed in material failure by fatigue fracture?
Plastic deformation of material does not occur
Initiation of crack from below the surface does not occur
Initiation of crack occurs on the surface of the machine part
Presence of both rough & smooth zone with conchoidal markings in smooth zone of the surface
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
With decrease in the grain size of a material, its creep resistance
Increases
Decreases
Remain constant
Either (A) or (B); depends on the material
Nickel is a __________ material.
Ferromagnetic
Semi-conductor
Paramagnetic
Ferroelectric
Carnot cycle is also termed as the constant __________ cycle in thermodynamics.
Entropy
Pressure
Volume
Heat