Heat flow across a hollow sphere of inner radius 'r₁' and outer radius 'r₂' is directly proportional to

Question

Heat flow across a hollow sphere of inner radius 'r₁' and outer radius 'r₂' is directly proportional to

A. (r₂ - r₁)/r₁. r₂

B. r₁. r₂/(r₂- r₁)

C. (r₂ + r₁)/r₁. r₂

D. r₁. r₂/(r₂ + r₁)

Share this question with your friends

Show all Chemical Engineering Basics MCQ

Comment

Good design of the casing of a centrifugal pump aims at minimising the

A. Cavitation

B. Frictional losses

C. Kinetic energy loss

D. Static head

Discuss this answer

Angular displacement can be measured suitably by a

A. Shaft encoder

B. Linear variable differential transducer (LVDT)

C. Stroboscope

D. Tachometer

Discuss this answer

On being hit with a hammer, __________ will readily fracture.

A. Brass

B. Mild steel

C. Cast iron

D. Lead

Discuss this answer

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

Discuss this answer

Identify the false statement

A. Martensitic steels are less susceptible to pitting corrosion than austenitic steels

B. Pitting corrosion is usually very localised

C. Hydrogen embrittlement is facilitated by tensile stress

D. Stress corrosion cracking is facilitated by tensile stress

Discuss this answer

Coating thickness in case of galvanising of steel sheet generally corresponds to the deposition of __________ gms of zinc per of steel strip.

A. 5-10

B. 1000-1500

C. 120-500

D. 1500-3000

Discuss this answer

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

Discuss this answer

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

A. T₁/(T₁-T₂)

B. T₂/(T₁-T₂)

C. T₁/T₂

D. T₂/T₁

Discuss this answer

The yield point phenomenon observed in annealed low carbon steel is due to the presence of the following element.

A. Silicon

B. Carbon

C. Phosphorous

D. Chromium

Discuss this answer

Baffles provided on the shell side of a shell and tube heat exchanger are meant for

A. Providing support for the tubes

B. Improving heat transfer

C. Both 'a' & 'b'

D. Preventing the fouling of tubes & stagnation of shell side fluid

Discuss this answer

For a small scale toy factory, the fixed cost per month is Rs. 5000/-. The variable cost per toy is Rs. 20 and sales price is Rs. 30 per toy. The break even production per month will be __________ toys.

A. 250

B. 500

C. 1000

D. 3000

Discuss this answer

Lead is poured into the joints between two __________ pipes.

A. Cast iron

B. Steel

C. Concrete

D. Plastic

Discuss this answer

The surface tension of a liquid, at critical temperature is

A. Indeterminate

B. Zero

C. Infinity

D. Same as that at any other temperature

Discuss this answer

Oxyacetylene reducing flame is used while carrying out welding on

A. Alloy steel

B. Grey cast iron

C. Mild steel

D. High carbon steel

Discuss this answer

Which of the, following is not associated with the functioning of a petrol engine?

A. Compression ignition system

B. Spark plug

C. Carburettor

D. Otto cycle

Discuss this answer

Other parameters remaining same, the recrystallisation temperature of an alloy is lowered, when

A. Strain rate is increased

B. Grain size is increased

C. Prior cold deformation is increased

D. Not affected by any of the above parameters

Discuss this answer

A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre.

A. 0.01

B. 0.1

C. 0.25

D. 0.5

Discuss this answer

Which of the following is the most wear resistant grade of carbide used for the cutting tools?

A. Aluminium carbide

B. Tungsten carbide

C. Nickel carbide

D. Iron carbide

Discuss this answer

Which of the following test is used for distinguishing among dry oils, semi-drying oils and non drying oils?

A. Elaiden test

B. Reichert-Meissl value test

C. Hunter value test

D. Iodine value test

Discuss this answer

Dislocations are __________ defects.

A. Point

B. Line

C. Volume

D. None of these

Discuss this answer

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.

A. 2

B. 8

C. 10

D. 40

Discuss this answer

The most abundant metal present in the earth's crust is;

A. Iron

B. Copper

C. Titanium

D. Aluminium

Discuss this answer

Large diameter reinforced cement concrete (RCC) pipes are generally joined by __________ joint.

A. Flanged iron

B. Collar

C. Flexible

D. Expansion

Discuss this answer

__________ property of a material is determined by the Herbert Pendulum device.

A. Hardness

B. Tensile

C. Toughness

D. Compressive

Discuss this answer

The material used for coating the welding electrode is termed as the

A. Flux

B. Slag

C. Protective layer

D. Binder

Discuss this answer

Leakage in a cooking gas cylinder is detected by

A. Radio-isotopes

B. Pouring soap solution on the surface and locating the gas bubbles

C. Halide torch

D. Pungent smell of mercaptans present in the gas

Discuss this answer

Metalloids

A. Are good conductor of heat & electricity

B. Act as electron donors with metals & as electron acceptor with non-metals

C. Are not necessarily solids at room temperature

D. Are compounds that exhibit both metallic & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron

Discuss this answer

Between 230 and 370°C, blue brittleness is caused in mild steel because of the

A. Immobility of dislocation

B. Strain-ageing

C. Increase in Young's modulus

D. Strain hardening

Discuss this answer

Unbreakable crockeries are made from __________ polymers.

A. Polystyrene

B. Melamine

C. Polystyrene

D. Polyurethane

Discuss this answer

The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________ BTU/hr.

A. 100

B. 200

C. 1000

D. 2000

Discuss this answer

Accepted Answer

B. r₁. r₂/(r₂- r₁)

Heat flow across a hollow sphere of inner radius 'r₁' and outer radius 'r₂' is directly proportional to

Correct Answer :

Show all Chemical Engineering Basics MCQ

Related Questions

Good design of the casing of a centrifugal pump aims at minimising the

Angular displacement can be measured suitably by a

On being hit with a hammer, __________ will readily fracture.

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

Identify the false statement

Coating thickness in case of galvanising of steel sheet generally corresponds to the deposition of __________ gms of zinc per of steel strip.

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.

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

The yield point phenomenon observed in annealed low carbon steel is due to the presence of the following element.

Baffles provided on the shell side of a shell and tube heat exchanger are meant for

For a small scale toy factory, the fixed cost per month is Rs. 5000/-. The variable cost per toy is Rs. 20 and sales price is Rs. 30 per toy. The break even production per month will be __________ toys.

Lead is poured into the joints between two __________ pipes.

The surface tension of a liquid, at critical temperature is

Oxyacetylene reducing flame is used while carrying out welding on

Which of the, following is not associated with the functioning of a petrol engine?

Other parameters remaining same, the recrystallisation temperature of an alloy is lowered, when

A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre.

Which of the following is the most wear resistant grade of carbide used for the cutting tools?

Which of the following test is used for distinguishing among dry oils, semi-drying oils and non drying oils?

Dislocations are __________ defects.

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.

The most abundant metal present in the earth's crust is;

Large diameter reinforced cement concrete (RCC) pipes are generally joined by __________ joint.

__________ property of a material is determined by the Herbert Pendulum device.

The material used for coating the welding electrode is termed as the

Leakage in a cooking gas cylinder is detected by

Metalloids

Between 230 and 370°C, blue brittleness is caused in mild steel because of the

Unbreakable crockeries are made from __________ polymers.

The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________ BTU/hr.

Also checkout

Heat flow across a hollow sphere of inner radius 'r1' and outer radius 'r2' is directly proportional to

Correct Answer :

Show all Chemical Engineering Basics MCQ

Related Questions

Good design of the casing of a centrifugal pump aims at minimising the

Angular displacement can be measured suitably by a

On being hit with a hammer, __________ will readily fracture.

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

Identify the false statement

Coating thickness in case of galvanising of steel sheet generally corresponds to the deposition of __________ gms of zinc per of steel strip.

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.

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

The yield point phenomenon observed in annealed low carbon steel is due to the presence of the following element.

Baffles provided on the shell side of a shell and tube heat exchanger are meant for

For a small scale toy factory, the fixed cost per month is Rs. 5000/-. The variable cost per toy is Rs. 20 and sales price is Rs. 30 per toy. The break even production per month will be __________ toys.

Lead is poured into the joints between two __________ pipes.

The surface tension of a liquid, at critical temperature is

Oxyacetylene reducing flame is used while carrying out welding on

Which of the, following is not associated with the functioning of a petrol engine?

Other parameters remaining same, the recrystallisation temperature of an alloy is lowered, when

A furnace is made of a refractory brick wall of thickness 0.5 metre and thermal conductivity 0.7 W/m.°K For the same temperature drop and heat loss, this refractory wall can be replaced by a layer of diatomaceous earth of thermal conductivity 0.14 W/m.K and thickness __________ metre.

Which of the following is the most wear resistant grade of carbide used for the cutting tools?

Which of the following test is used for distinguishing among dry oils, semi-drying oils and non drying oils?

Dislocations are __________ defects.

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.

The most abundant metal present in the earth's crust is;

Large diameter reinforced cement concrete (RCC) pipes are generally joined by __________ joint.

__________ property of a material is determined by the Herbert Pendulum device.

The material used for coating the welding electrode is termed as the

Leakage in a cooking gas cylinder is detected by

Metalloids

Between 230 and 370°C, blue brittleness is caused in mild steel because of the

Unbreakable crockeries are made from __________ polymers.

The cooling rate required to freeze 1 ton of water at 0°C into ice at 0°C in 24 hours is __________ BTU/hr.

Also checkout

Heat flow across a hollow sphere of inner radius 'r₁' and outer radius 'r₂' is directly proportional to

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

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.