Explore topic-wise InterviewSolutions in .

This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.

1.

Which of the following is not a property pf wrought iron?(a) Wrought iron is ductile and malleable(b) It fuses easily(c) The specific gravity of wrought iron is about 7.8(d) Wrought iron can be easily forged and weldedThis question was addressed to me at a job interview.Origin of the question is Ferrous Metals topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct option is (b) It fuses easily

Easy EXPLANATION: Wrought iron is DUCTILE and malleable. Wrought iron fuses with difficulty but it can be easily forged and WELDED. The specific GRAVITY of wrought iron is about 7.8.

2.

Aston’s process is used to manufacture _________(a) Steel(b) Wrought iron(c) Pig iron(d) Cast ironI have been asked this question in an online interview.This interesting question is from Ferrous Metals topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct answer is (b) Wrought iron

For explanation: Aston’s process was DEVELOPED by James Aston in 1925. It is USED to manufacture wrought iron and in a quick and economical WAY. Aston’s process is fully mechanical.

3.

The material obtained at the end of the shingling process is called as ________(a) Flux(b) Slag(c) Bloom(d) FuseI have been asked this question in an interview for job.This intriguing question originated from Ferrous Metals topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct CHOICE is (c) Bloom

The best I can explain: The PROCESS of shingling is used to REMOVE the slag contained in the puddle balls. The material obtained at the end of the shingling process is called bloom. The bloom is then passed through grooved rollers to order to obtain flat bars which indicate WROUGHT iron of poor quality.

4.

The process of puddling is carried out in a ________(a) Blast furnace(b) Flask(c) Cupola furnace(d) Reverberatory furnaceThis question was posed to me during an online exam.This interesting question is from Ferrous Metals topic in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right option is (d) Reverberatory furnace

Easy explanation: The process of puddling is carried out in a reverberatory furnace. The metal does not come in CONTACT with the FUEL in a reverberatory furnace. This type of furnace is rectangular in SHAPE and BUILT with refractory materials like fire-bricks.

5.

The process of converting pig iron into wrought iron by stirring in the molten state is called as _________(a) Puddling(b) Refining(c) Rolling(d) ShinglingI had been asked this question during a job interview.I need to ask this question from Ferrous Metals in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right choice is (a) PUDDLING

The best explanation: There are four operations INVOLVED in the manufacturing of wrought iron. These are refining, puddling, shingling and rolling. The process of converting PIG iron into wrought iron by stirring in the MOLTEN state is CALLED puddling.

6.

Which of the following statements about low shaft blast furnace is not true?(a) In this, the blast is rich in oxygen(b) The gas produced has a low calorific value(c) The oxygen consumed by this furnace can be made available from natural air(d) It consumes fine oresI had been asked this question in final exam.My question is taken from Ferrous Metals in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right OPTION is (b) The gas produced has a low calorific VALUE

For explanation: In a low shaft blast furnace, the blast is rich in oxygen. The oxygen consumed by this furnace can be MADE available from NATURAL air. It consumes FINE ores and the gas produced has high calorific value.

7.

Which chemical is used in the method of parkerizing, adopted to prevent corrosion?(a) Alum(b) Borax(c) Pareo(d) VitriolThis question was addressed to me in an interview for job.The above asked question is from Ferrous Metals topic in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right CHOICE is (c) Pareo

To explain I would say: In the method of parkerizing, adopted to prevent CORROSION, the article to be TREATED for corrosion is immersed in a hot water bath of a CHEMICAL called Pareo. Insoluble phosphates are created on the surface of the article which keeps away the moisture.

8.

Corrosion of ferrous metals is known as ___________(a) Enamelling(b) Rusting(c) Galvanising(d) Coal TarringThis question was posed to me in an interview.The origin of the question is Ferrous Metals in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The CORRECT option is (b) Rusting

Best explanation: CORROSION of FERROUS metals is known as rusting. Rusting of cast iron is less and rusting of wrought iron is medium while that of steel is found to be MUCH more. Enamelling, coal tarring and galvanising are some of the METHODS used to prevent corrosion.

9.

Dust of pure _________ is used to cover the article to be treated for corrosion in the method of sherardising.(a) Platinum(b) Zinc(c) Copper(d) BariumThis question was posed to me in homework.I want to ask this question from Ferrous Metals topic in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct OPTION is (b) ZINC

Easy explanation: Dust of pure zinc is used to cover the article to be TREATED for corrosion in the method of sherardising. It is then HEATED to a suitable temperature in an airtight steel box which results in the melting of zinc. It then combines with the metal and CREATES a protective layer on its surface and thus prevents it from rusting.

10.

Which metal is used in the galvanisation of iron in order to prevent it from rusting?(a) Zinc(b) Sodium(c) Copper(d) SilverI got this question in final exam.This interesting question is from Ferrous Metals in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct OPTION is (a) Zinc

For explanation: Zinc is USED in the GALVANISATION of iron in order to PREVENT it from rusting. The LAYER of zinc is more reactive than iron, and hence it cuts the contact of iron with air or moisture and protects it from rusting.

11.

In which type of casting, the outer surface is made hard while the inner surface remains relatively soft?(a) Hollow casting(b) Sand casting(c) Chilled casting(d) Die castingThis question was addressed to me during an online interview.My doubt stems from Ferrous Metals topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right option is (c) Chilled casting

To EXPLAIN I WOULD say: In chilled casting, the outer surface is made hard while the inner surface remains relatively soft. SUDDEN cooling or chilling makes the outer surface hard. Chilled casting is used for PRODUCING wearing surface as in case of tyres.

12.

In which type of casting, molten metal is poured into moulds which keep on rotating?(a) Centrifugal casting(b) Chilled casting(c) Hollow casting(d) Sand castingThis question was addressed to me in homework.The query is from Ferrous Metals in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct ANSWER is (a) Centrifugal casting

The explanation is: There are various TYPES of CASTINGS. These are centrifugal casting, chilled casting, hollow casting, sand casting, die casting and VERTICAL sand casting. Molten metal is POURED into moulds which keep on rotating in centrifugal casting. Centrifugal casting is usually used to prepare pipes.

13.

Grey pig is produced when the blast furnace is not provided with sufficient fuel while the white pig is produced when the blast furnace is provided sufficiently with fuel.(a) True(b) FalseI have been asked this question during an online exam.The above asked question is from Ferrous Metals in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right option is (b) False

The explanation: The white PIG is PRODUCED when the blast furnace is not PROVIDED with sufficient fuel while the grey pig is produced when the blast furnace is provided sufficiently with fuel. White pig is USED in the manufacturing of wrought iron.

14.

Thermal damping is given by the equation D = (T-t/T) x 100. Here, T denotes _________(a) Outside temperature range(b) Inside temperature range(c) Total outside and inside temperature range(d) ThicknessThis question was addressed to me in homework.Question is taken from Thermal Insulation topic in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct answer is (a) Outside TEMPERATURE RANGE

The explanation: Thermal damping is GIVEN by the equation D = (T-t/T) x 100. Here, T denotes outside temperature range and t denotes inside temperature range. Also, thermal damping is denoted by D.

15.

Which variety of cast iron is obtained by melting cast iron with wrought iron scrap?(a) Mottled cast iron(b) Chilled cast iron(c) Malleable cast iron(d) Toughened cast ironI have been asked this question in final exam.I'm obligated to ask this question of Ferrous Metals in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer» RIGHT answer is (d) TOUGHENED cast iron

For explanation: MELTING cast iron with wrought iron scrap results in the FORMATION of toughened cast iron. Mottled cast iron is an intermediate between white cast iron and GREY cast iron.
16.

Smelting is carried out in a ___________(a) Funnel(b) Kiln(c) Blast furnace(d) FlaskThe question was posed to me in a job interview.My query is from Ferrous Metals in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»
17.

Room air conditioners and packaged units are examples of _________(a) Direct expansion systems(b) Indirect expansion systems(c) Chilled water systems(d) Indirect contraction systemsI had been asked this question during an internship interview.My query is from Systems and Essentials of Air Conditioning System in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right choice is (a) Direct EXPANSION systems

For EXPLANATION: Air CONDITIONING systems are classified into two categories. These are direct expansion systems and CHILLED water systems. Room air conditioners and packaged units are examples of direct expansion systems.

18.

According to Indian Standards, overall thermal transmittance of a wall should not be more than __________ kcal/m^2 h deg C.(a) 1.3(b) 2.2(c) 3.7(d) 4.6This question was posed to me by my college professor while I was bunking the class.My question comes from Thermal Insulation topic in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct option is (b) 2.2

To explain I WOULD say: According to Indian STANDARDS, overall thermal transmittance of a WALL should not be more than 2.2 kcal/m^2 h deg C. Heat insulation of EXPOSED walls can be ACHIEVED by increasing the thickness of the wall.

19.

Rate of the burning of a good fuse is ___________(a) 1 mm/sec(b) 1 cm/sec(c) 1 m/sec(d) 1 cm/hThe question was asked in a job interview.This is a very interesting question from Stones topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The CORRECT choice is (B) 1 cm/sec

Explanation: A fuse is USED to ignite the explosives. The RATE of burning of a good fuse is 1 cm/sec.

20.

According to the Indian Standards, it is recommended that thermal damping of a wall should not be less than _______(a) 40%(b) 50%(c) 60%(d) 80%The question was posed to me during a job interview.My doubt is from Thermal Insulation topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct CHOICE is (c) 60%

Explanation: ACCORDING to the Indian Standards, it is recommended that the thermal damping of a wall should not be LESS than 60%. Hence, it is also recommended that the thermal time CONSTANT should not be less than 16 h.

21.

The process of extraction of the certain required amount of water from air is known as ___________(a) Heating(b) Cooling(c) Humidification(d) DehumidificationI have been asked this question in a job interview.Question is from Systems and Essentials of Air Conditioning System in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct answer is (d) Dehumidification

The best explanation: The PROCESS of extraction of a certain required amount of WATER from AIR is known as dehumidification. This can be achieved by condensation or desiccation. HUMIDIFICATION is the addition of water to air.

22.

Commonly used fluxing material used in the process of smelting is ___________(a) Limestone(b) Sandstone(c) Concrete(d) CementThe question was asked in homework.Question is from Ferrous Metals topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct choice is (a) Limestone

Explanation: COMMONLY used fluxing MATERIAL used in the process of smelting is limestone. Fluxing material is a SUBSTANCE that can be readily FUSED and mixes with the impurities present in the ores of IRON and forms a fusible slag.

23.

Cutting of stones into suitable sizes with suitable surfaces after quarrying is known as ___________ of stones.(a) Painting(b) Dressing(c) Blasting(d) WedgingI got this question in an interview for internship.My question comes from Stones topic in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct answer is (B) Dressing

For explanation I would say: Cutting of STONES into SUITABLE SIZES with suitable SURFACES after quarrying is known as dressing of stones. It is carried out in order to get the desired appearance from stonework.

24.

Which of the following facts about gypsum is not correct?(a) It is hydrated sulphate of calcium(b) It has excellent solubility in water(c) It is white in the pure state(d) Its solubility in water is extremely poorI had been asked this question in an interview.My question is taken from Stones in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct choice is (b) It has EXCELLENT solubility in WATER

Easy explanation: Gypsum is hydrated SULPHATE of calcium. It is WHITE in the pure state. Its solubility in water is extremely poor.

25.

____________ is the process of taking out stones from natural rock beds.(a) Normalising(b) Quarrying(c) Mining(d) SmeltingI have been asked this question in an online interview.I'm obligated to ask this question of Stones in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The CORRECT option is (b) Quarrying

Easiest explanation: Quarrying is the process of taking out stones from natural ROCK BEDS. Stones OBTAINED from quarrying are widely used for VARIOUS engineering purposes.

26.

The toughness of stone is said to be high if the value of the toughness index exceeds __________(a) 7(b) 13(c) 15(d) 19I got this question by my school teacher while I was bunking the class.The above asked question is from Stones topic in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The CORRECT choice is (d) 19

The explanation: Toughness of stone is SAID to be high if the value of the toughness index exceeds 19. If it is below 13, then the stone is not tough and if it is between 13 and 19, then the stone is MODERATELY tough.

27.

Which of the following is also called white mica?(a) Biotite(b) Felspar(c) Muscovite(d) MicrolineThis question was addressed to me during an interview.The query is from Stones topic in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right CHOICE is (c) Muscovite

The explanation: There are two forms of MICA which commonly occur in IGNEOUS rocks. These are biotite and muscovite. Muscovite is also CALLED WHITE mica and biotite is also called black mica.

28.

Which of the following is not a quality of a good thermal insulating material?(a) It should be durable(b) It should have a low thermal resistance(c) It should be readily available(d) It should be fireproofThe question was asked in a job interview.I'd like to ask this question from Thermal Insulation in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct option is (b) It should have a low THERMAL resistance

To explain I would say: A GOOD thermal insulating material should be DURABLE. It should have HIGH thermal resistance. It should be fireproof and readily available.

29.

In a chilled water system, the refrigerant is used to cool the air directly while in the direct expansion system, a secondary medium like water is used to cool the air.(a) True(b) FalseI have been asked this question in my homework.I would like to ask this question from Systems and Essentials of Air Conditioning System topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct option is (b) False

Easy EXPLANATION: In the direct expansion system, the refrigerant is used to cool the air directly while in the chilled WATER system, a secondary medium like water is used to cool the air. In the chilled water system, the refrigerant FIRST COOLS the water and then the water cools the air.

30.

For a stone to be used in road work, coefficient of hardness should be greater than ___________(a) 7(b) 10(c) 15(d) 17The question was posed to me by my college director while I was bunking the class.This interesting question is from Stones in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right choice is (d) 17

The best explanation: For a stone to be used in road work, coefficient of hardness should be greater than 17. The stone is SAID to be of medium hardness if the coefficient of hardness lies between 14 and 17. However, if the coefficient of hardness is less than 14, then the stone is said to be of POOR hardness and therefore should not be used in road work.

31.

The manganese content in cast iron should be kept below __________(a) 0.75%(b) 1%(c) 1.5%(d) 1.75%The question was asked during an interview for a job.This key question is from Ferrous Metals in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct answer is (a) 0.75%

Easiest explanation: Presence of manganese makes CAST iron hard and BRITTLE. THEREFORE, manganese content in cast iron should be kept below 0.75%.

32.

Which of the following is the hottest part of the blast furnace?(a) Throat(b) Stack(c) Bosh(d) CylinderThis question was posed to me in unit test.Asked question is from Ferrous Metals in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct option is (c) Bosh

Easy explanation: Bosh the hottest PART of the BLAST FURNACE. It is the BURNING ZONE of the furnace. Bosh is located between the cylinder and the hearth.

33.

The crude impure iron extracted from the ores of iron is called as __________(a) Cast iron(b) Wrought iron(c) Steel(d) Pig ironThe question was posed to me in quiz.Origin of the question is Ferrous Metals in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct answer is (d) Pig iron

Explanation: Pig iron is the crude IMPURE iron extracted from the ores of iron. Pig iron is one of the basic materials USED in the manufacturing of STEEL, wrought iron as well as CAST iron.

34.

Which tool is used to make blast holes in the process of blasting?(a) Dipper(b) Tamping bar(c) Jumper(d) NeedleThis question was posed to me during an online exam.This intriguing question comes from Stones topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»
35.

The acid test used for testing building stones cannot be applied to limestones.(a) True(b) FalseI got this question in an online quiz.The question is from Stones topic in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct OPTION is (a) True

The BEST EXPLANATION: Acid test USED for TESTING building stones cannot be applied to limestones. It is generally carried out on sandstones.

36.

Which of the following is the correct relation between thermal transmittance and thermal time constant?(a) T = Q x U(b) T = k/U(c) T = Q/U(d) T = U/QThis question was posed to me in class test.I'm obligated to ask this question of Thermal Insulation topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»
37.

Viscous type filters are made of screens of spilt wire and coated with non-drying viscous oil in order to catch and remove the dust particles from the incoming air.(a) True(b) FalseI got this question in quiz.The above asked question is from Systems and Essentials of Air Conditioning System topic in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right answer is (a) True

The explanation: Viscous type filters are made of SCREENS of spilt WIRE and coated with non-drying viscous OIL in order to catch and remove the DUST particles from the INCOMING air. They can be of two types – unit type or automatic type.

38.

Blasting powder is a mixture of _____________(a) Charcoal, sulphur and saltpetre(b) Aluminium, phosphorus and saltpetre(c) Charcoal, calcium and phosphorus(d) Sodium, sulphur and alumI have been asked this question in unit test.Asked question is from Stones topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer» RIGHT answer is (a) Charcoal, SULPHUR and saltpetre

Best explanation: Blasting POWDER is a mixture of charcoal, sulphur and saltpetre. It is also KNOWN as gun powder and is commonly USED as an explosive in the process of blasting.
39.

Quartz sand is an example of polymineralic rock while granite is an example of a monomineralic rock.(a) True(b) FalseThis question was posed to me during an interview.My question comes from Stones topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct answer is (b) False

To EXPLAIN I would say: Quartz sand is an EXAMPLE of monomineralic rock while GRANITE is an example of a polymineralic rock. A monomineralic rock consists of only ONE mineral while a polymineralic rock consists of many minerals.

40.

Reflective sheet materials used as thermal insulating material have ___________ reflectivity and __________ emissivity.(a) High, high(b) High, low(c) Low, low(d) Low, highThis question was posed to me in examination.Origin of the question is Thermal Insulation topic in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right ANSWER is (b) High, low

Easiest EXPLANATION: Reflective sheet materials used as thermal INSULATING material have high reflectivity and low emissivity. Because of this property, it OFFERS high heat RESISTANCE.

41.

Presence of moisture in the thermal insulating material increases thermal insulation while the presence of air spaces decreases thermal insulation.(a) True(b) FalseI had been asked this question during an internship interview.Origin of the question is Thermal Insulation in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Correct ANSWER is (b) False

To explain I would say: PRESENCE of moisture in the thermal insulating material decreases thermal insulation while the presence of air spaces increases thermal insulation. The choice of the thermal insulating material depends on various factors LIKE cost of material, area to be covered, coat of heating or cooling, etc.

42.

Which of the following is not a component of packaged air conditioners?(a) Compressor(b) Condenser(c) Chiller(d) EvaporatorThe question was posed to me during an interview.The question is from Systems and Essentials of Air Conditioning System in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer» RIGHT answer is (c) Chiller

Best explanation: Packaged AIR CONDITIONERS consist of a compressor, condenser, evaporator and a fan. Unlike packaged air conditioners, chilled water system consists of an additional ITEM CALLED the chiller.
43.

Which of the following qualities is not possessed by the filters in the air conditioning system?(a) They should be capable of removing dust particles from the incoming air(b) They should afford easy cleaning(c) They should offer low frictional resistance to the airflow(d) They should offer high frictional resistance to the airflowThe question was asked by my college director while I was bunking the class.The doubt is from Systems and Essentials of Air Conditioning System in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The correct option is (d) They should offer high frictional resistance to the airflow

Explanation: The filters in the AIR conditioning SYSTEM should be capable of removing DUST PARTICLES from the incoming air. They should AFFORD easy cleaning and should offer low frictional resistance to the airflow.

44.

Which of the following is not a classification of rocks from which building stones are obtained?(a) Geological classification(b) Biological classification(c) Physical classification(d) Chemical classificationI have been asked this question during an online interview.My enquiry is from Stones in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»
45.

Thermal insulation keeps the room cool in winters and hot in summers.(a) True(b) FalseThe question was asked during an interview.This interesting question is from Thermal Insulation topic in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

The CORRECT choice is (b) False

Explanation: Thermal insulation keeps the ROOM hot in WINTERS and cool in summers which results in comfortable living. It minimises heat TRANSFER and helps in saving fuel to maintain the DESIRED temperature in the room.

46.

Dolerite is an example of ________ rock.(a) Plutonic(b) Sedimentary(c) Hypabyssal(d) VolcanicThe question was asked by my college director while I was bunking the class.Asked question is from Stones in division Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right answer is (c) Hypabyssal

The EXPLANATION: Dolerite is an example of a hypabyssal rock. Hypabyssal rocks are types of igneous rocks which are FORMED due to colling of MAGMA at comparatively shallow DEPTH from the SURFACE of the earth.

47.

Cordite is prepared from ___________(a) Benzene(b) Nitro-glycerine(c) Phenol(d) EsterI got this question by my school teacher while I was bunking the class.I'm obligated to ask this question of Stones topic in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right CHOICE is (b) Nitro-glycerine

Easiest explanation: CORDITE is prepared from nitro-glycerine. It is a POWERFUL explosive used in the BLASTING process and it can be used under water.

48.

The use of explosives in order to convert rocks into small pieces of stones is done in ___________(a) Wedging(b) Heating(c) Digging(d) BlastingThis question was posed to me in a job interview.My query is from Stones in chapter Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»

Right choice is (d) BLASTING

Explanation: The use of explosives in order to convert rocks into SMALL pieces of STONES is done in blasting. Blasting is used for quarrying hard stones without having any fissures or cracks. Stones obtained by this METHOD are generally of small size.

49.

Which of the following is the correct relationship between thermal resistance and thermal conductivity?(a) R = k/L(b) R = k.L(c) R = L/k(d) R = L^2/kI had been asked this question by my college professor while I was bunking the class.My question is based upon Thermal Insulation in section Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer»
50.

Which of the following is not a property of cast iron?(a) Cast iron is hard but brittle(b) Cast iron can be magnetised(c) It does not rust readily(d) Cast iron is not ductileThis question was addressed to me in class test.Asked question is from Ferrous Metals in portion Air Conditioning, Thermal Insulation, Stones & Ferrous Metals of Construction & Building Materials

Answer» CORRECT option is (b) Cast IRON can be MAGNETISED

Explanation: Cast iron is hard but brittle. It is not DUCTILE and does not RUST readily. Cast iron cannot be magnetised.