Home
Current Affairs January 2024

What is the correct answer?

4

__________ of grey cast iron produces white cast iron.

A. Tempering

B. Rapid heating

C. Rapid cooling

D. Slow cooling

Correct Answer :

B. Rapid heating


Related Questions

What is the correct answer?

4

Super conduction in metals is observed at a temperature of __________ °K.

A. <100

B. >100

C. About 273

D. About 373

What is the correct answer?

4

Thermit welding is categorised as the __________ welding.

A. Forge

B. Fusion

C. Resistance

D. Arc

What is the correct answer?

4

Eutectic reaction for iron-carbon system occurs at a temperature of __________ °C.

A. 723

B. 959

C. 1147

D. 1493

What is the correct answer?

4

Globular form of cementite is formed during the __________ process.

A. Spheroidising

B. Hardening

C. Annealing

D. Normalising

What is the correct answer?

4

Thermit welding uses the following energy source.

A. Electrical energy

B. Chemical energy

C. Energy of high velocity electrons

D. Heat generated by friction

What is the correct answer?

4

Evaporative cooling process employs a combination of cooling and humidification in which the

A. Sensible heat is added

B. Sensible heat is removed and the latent heat is added

C. Latent heat is removed

D. Sensible heat is added and latent heat is removed

What is the correct answer?

4

The majority charge carriers in p-type silicon are

A. Free electrons

B. Ions

C. Conduction electrons

D. Holes

What is the correct answer?

4

Consideration of the creep is the most important in case of the

A. Blades of gas turbine

B. Piston of an I. C. engine

C. Flywheel of steam engine

D. Cycle chain

What is the correct answer?

4

If a solid is compressed adiabatically in its elastic range, its __________ remains constant

A. Internal energy

B. Enthalpy

C. Entropy

D. Temperature

What is the correct answer?

4

Inertial forces are obtained, when the elastic forces are multiplied by __________ number.

A. Mach

B. Froude

C. Reynolds

D. Euler

What is the correct answer?

4

The expected efficiency of a single riveted lap joint is of the order of 50%. If the thickness of the plate is increased four times, then the rivet diameter will have to be increased __________ times.

A. Two

B. Four

C. Six

D. Eight

What is the correct answer?

4

A material being tested for endurance strength is subjected to the __________ load.

A. Impact

B. Completely reversed

C. Dynamic

D. Static & dynamic

What is the correct answer?

4

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.

A. 15

B. 25

C. 10

D. 30

What is the correct answer?

4

The mechanism involved in the removal of metal in drilling operation is by

A. Compression

B. Extrusion

C. Shearing

D. Both 'b' & 'c'

What is the correct answer?

4

M10 index of coke indicates its

A. Compressive strength

B. Hardness

C. Abrasion resistance

D. Impact strength

What is the correct answer?

4

Electrometallurgical methods of metal extraction is normally used for those metals

A. Whose oxide/ore is not reduced by carbon

B. Which fall in the category of alkali & alkaline earth metals

C. Which stands higher in the electrochemical series of the metal

D. All (A), (B) & (C)

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

Larger length & diameter water pipes are made by

A. Electrical resistance welding

B. Die casting

C. Semi-centrifugal casting

D. Continuous casting

What is the correct answer?

4

Production of one ton of paper in Indian paper industry consumes about __________ kWh of electricity.

A. 300

B. 800

C. 1400

D. 2000

What is the correct answer?

4

Heating of ferromagnetic materials to a temperature above Curie temperature makes it

A. Insulator for heat & electricity transmission

B. Ferritic

C. Behave like paramagnetic materials

D. Superconductor

What is the correct answer?

4

Which of the following does not have a sharp melting point?

A. Thoria

B. Glass

C. Ice

D. Pig iron

What is the correct answer?

4

Venturimeter is used to measure the flow rate of fluids in pipes, when the pipe is in __________ position.

A. Horizontal

B. Vertical

C. Inclined

D. Any

What is the correct answer?

4

Pick out the wrong statement.

A. For a pressure vessel to be classified as 'thin vessel', the ratio of wall thickness to mean radius is less than 0.1

B. For calculating forces and efficiency of riveted joint, either rivet diameter or rivet hole diameter is used in case of pressure vessel and in structural work

C. Longitudinal joint is normally made butt joint to maintain the circularity of the vessel

D. Maximum diameter of the opening provided in a pressure vessel, which does not require any compensation is 200 mm

What is the correct answer?

4

The most important function of a washer is to provide bearing area and washers are normally specified by their hole diameters. The diameter of washer as compared to the nut is

A. More

B. Less

C. Same

D. More but less than the diameter of bolt

What is the correct answer?

4

Temperature attained in soldering of metals is about __________ °C.

A. 150-300

B. 400-500

C. 650-800

D. 1000-1100

What is the correct answer?

4

Which of the following is an unconventional source of energy?

A. Thermal power

B. Hydroelectric power

C. Nuclear-fusion power

D. Solar power

What is the correct answer?

4

Auto collimator is used to check

A. Flatness

B. Angle

C. Rotor balancing

D. Roughness

What is the correct answer?

4

Gross national product (GNP) means the total value of __________ in a country.

A. Goods produced

B. Gold reserve

C. Earning of the citizens

D. Taxes paid

What is the correct answer?

4

Transformer cores are normally made from

A. Soft ferrites

B. High purity iron

C. Grain oriented Fe-Si alloy

D. Al-Ni-Co alloy

What is the correct answer?

4

Austempering of steel requires it to be heated to 875°C followed by sudden cooling to 250-525°C, thereby changing austenite to

A. Sorbite

B. Bainite

C. Martensite

D. Troostite