Home
Current Affairs January 2024

What is the correct answer?

4

Machinability of hard alloys and tool steels is improved by

A. Spheroidising

B. Annealing

C. Tempering

D. Normalising

Correct Answer :

B. Annealing


Related Questions

What is the correct answer?

4

For the Stoke's law to be valid in the case of a falling sphere in a fluid, the

A. Reynolds number (based on sphere diameter) should be < 1

B. Flow around the sphere should be in turbulent region

C. Sphere must be metallic

D. Fluid density should be constant

What is the correct answer?

4

Potable water means the water used for

A. Fire-fighting

B. Cooling

C. Drinking

D. Evaporation to produce steam

What is the correct answer?

4

The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K)

A. T

B. 1/T

C. T2

D. 1/T2

What is the correct answer?

4

Lead is poured into the joint between two __________ pipes.

A. Mild steel

B. Concrete

C. Cast iron

D. Asbestos cement

What is the correct answer?

4

The diffusion co-efficient of Ni in Cu at 1000 K is 1.93 × 10-16 m2S-1 and it is 1.94 × 10-14 m2S- 1 at 1200 K. The activation energy (in k. J.mole-1) for the diffusion of Ni in Cu is

A. 130

B. 180

C. 230

D. 250

What is the correct answer?

4

Ammonia leakage in the refrigeration system is detected by

A. Sulphur stick, which on detection gives white smoke

B. Using chemical reagents

C. Its smell

D. Soap solution

What is the correct answer?

4

The softness or hardness of a grinding wheel depends upon the type & amount of bonding material used. For general purpose cutter grinding __________ grinding wheel is normally used.

A. Hard

B. Soft

C. Silicon carbide

D. Aluminium oxide

What is the correct answer?

4

Stellite is a __________ material.

A. Ferrous

B. Ceramic

C. Cemented carbide

D. Non-ferrous cast alloy cutting tool

What is the correct answer?

4

The elastic strain energy of a unit length of an edge dislocation as compared to that of a screw dislocation is

A. More

B. Equal

C. Less

D. Double

What is the correct answer?

4

The materials which fracture even at small strains are termed as brittle, while those materials which exhibit an appreciable deformation before failure are termed as

A. Rigid

B. Tough

C. Ductile

D. Plastic

What is the correct answer?

4

The escape velocity of a body on earth which is independent of its mass is about __________ km/second.

A. 3

B. 7

C. 11

D. 15

What is the correct answer?

4

Pick out the wrong statement.

A. Cold cracking of a weld is due to the presence of hydrogen gas in the weld

B. True stress is given by, σ = σE (1 + εE), where σE and εE are engineering stress and engineering strain respectively

C. Phosphorous can be easily recovered in the iron blast furnace

D. High residual stress at the surface is beneficial for fatigue properties of a material

What is the correct answer?

4

For preparation of porous bearings by powder metallurgy, preferred particle shape is

A. Spherical

B. Nodular

C. Irregular

D. No preferred shape

What is the correct answer?

4

With increase in temperature, the electrical conductivity of a __________ decreases.

A. Semi-conductor

B. Metal or alloy

C. Dielectric

D. None of these

What is the correct answer?

4

Which of the following mainly decides the current to be employed is arc welding?

A. Electrode size

B. Plate thickness

C. Voltage across the arc

D. Welded portion length

What is the correct answer?

4

Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________ kJ.

A. +4000

B. -4000

C. 10000

D. -10000

What is the correct answer?

4

The bolt is subjected to __________ when the nut is tightened by putting the washer beneath it.

A. Tension

B. Shear

C. Compression

D. Bending & tension

What is the correct answer?

4

Limestone is added in the blast furnace (during pig iron manufacture) to

A. Form slag by combining with impurities

B. Supply heat by undergoing exothermic reaction with impurities

C. Reduce the coke consumption

D. Reduce slag viscosity

What is the correct answer?

4

The co-ordination number in simple cubic structure is

A. 4

B. 6

C. 8

D. 12

What is the correct answer?

4

Wrought iron does not have

A. Uniform strength in all directions

B. Ability to hold protective coating

C. High ductility & corrosion resistance

D. Easily weldable characteristics

What is the correct answer?

4

Which of the following is an acidic constituent of B.F. slag?

A.

B. FeO

C. MgO

D. CaO

What is the correct answer?

4

The fugacity of liquid water at 298 K is approximately 3171 Pa. Considering the ideal heat of vaporisation as 43723 J/gm.mole, its fugacity at 300 K would be

A. 3171Pa

B. 3567Pa

C. 1.01 × 105Pa

D. 5000Pa

What is the correct answer?

4

Which of the following is normally not found in both the S.I. (petrol) & C.I. (diesel) engines?

A. Air filter

B. Fuel injector

C. Exhaust silencer

D. Battery

What is the correct answer?

4

When the wavelength of incident X-rays increases, the angle of diffraction

A. Decreases

B. Increases

C. Remain constant

D. Shows no systematic variation

What is the correct answer?

4

Presence of nickel & chromium in steel does not raise its

A. Elastic limit

B. Machining properties

C. Ductility

D. Resilience

What is the correct answer?

4

Normalising of a casting does not

A. Induce stresses in it

B. Refine its grain structure

C. Reduce segregation

D. Improve its mechanical properties

What is the correct answer?

4

High endurance limit of carburised machine parts is because of the fact that carburisation

A. Suppresses any stress concentration produced in the parts

B. Enhances the yield point of the material

C. Introduces a compressive layer on the surface

D. Produces a better surface finish

What is the correct answer?

4

The passage between the nozzle and the __________ is called 'sprue' in case of injection moulding.

A. Runner

B. Cylinder

C. Mold

D. None of these

What is the correct answer?

4

Air/fuel ratio on molar (volume) basis for combustion of methane with theoretical quantity of air with be

A. 9.5 : 1

B. 12.5 : 1

C. 15.5 : 1

D. 18.5 : 1

What is the correct answer?

4

Heat transfer by __________ is almost absent in case of fluidised bed drying operation.

A. Radiation

B. Conduction

C. Convection

D. Both (B) & (C)