Bed pressure drop in an air fluidised bed of catalyst particles (ρp = 200 kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed in cm of water (manometer) is (A) 90 (B) 60 (C) 45 (D) 30

Bed pressure drop in an air fluidised bed of catalyst particles (ρp = 200
kg/m3, Dp = 0.05 cm) of 60 cm bed depth and bed porosity of 0.5 expressed
in cm of water (manometer) is
(A) 90
(B) 60
(C) 45
(D) 30
by

1 Answer

Answer :

(B) 60
by

Related questions

A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Description : A bed consists of particles of density 2000 kg/m3 . If the height of the bed is 1.5 metres and its porosity 0.6, the pressure drop required to fluidise the bed by air is (A) 25.61 kPa (B) 11.77 kPa (C) 14.86 kPa (D) 21.13 kPa

Last Answer : (B) 11.77 kPa

A gas (density = 1.5 kg/m3 , viscosity = 2 × 10 ‒5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5 kg/m3and viscosity of 3 × 10 ‒5kg/m.s flowing at 3 m/s will be (A) 8400 Pa/m (B) 12600 Pa/m (C) 18900 Pa/m (D) 16800 Pa/m

Description : A gas (density = 1.5 kg/m3 , viscosity = 2 10 -5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The ... flowing at 3 m/s will be (A) 8400 Pa/m (B) 12600 Pa/m (C) 18900 Pa/m (D) 16800 Pa/m

Last Answer : (B) 12600 Pa/m

. A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m3 ) is to be fluidised by water (density 1000 kg/m3 ). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is (A) 4.4 KPa (B) 2.94 KPa (C) 3.7 KPa (D) None of these

Description : . A 0.5 m high bed made up of a 1 mm dia glass sphere (density 2500 kg/m3 ) is to be fluidised by water (density 1000 kg/m3 ). If at the point of incipient fluidisation, the bed voidage is 40%, the pressure drop across the bed is (A) 4.4 KPa (B) 2.94 KPa (C) 3.7 KPa (D) None of these

Last Answer : (A) 4.4 KPa

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below: Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

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Last Answer : (C) 0.7

Fluidised bed reactor is characterised by (A) Uniformity of temperature (B) Comparatively smaller equipment (C) Very small pressure drop (D) Absence of continuous catalyst regeneration facility

Description : Fluidised bed reactor is characterised by (A) Uniformity of temperature (B) Comparatively smaller equipment (C) Very small pressure drop (D) Absence of continuous catalyst regeneration facility

Last Answer : (A) Uniformity of temperature

Hot water (0.01 m3 /min) enters the tube side of a counter current shell and tube heat exchanger at 80°C and leaves at 50°C. Cold oil (0.05 m3 /min) of density 800 kg/m3 and specific heat of 2 kJ/kg.K enters at 20°C. The log mean temperature difference in °C is approximately (A) 32 (B) 37 (C) 45 (D) 50

Description : Hot water (0.01 m3 /min) enters the tube side of a counter current shell and tube heat exchanger at 80°C and leaves at 50°C. Cold oil (0.05 m3 /min) of density 800 kg/m3 and specific heat of ... mean temperature difference in °C is approximately (A) 32 (B) 37 (C) 45 (D) 50

Last Answer : (A) 32

Minimum porosity for fluidisation is(A) That corresponding to static bed (B) That corresponding to completely fluidised bed (C) The porosity of the bed when true fluidisation begins (D) Less than that of the' static bed

Description : Minimum porosity for fluidisation is (A) That corresponding to static bed (B) That corresponding to completely fluidised bed (C) The porosity of the bed when true fluidisation begins (D) Less than that of the' static bed

Last Answer : (C) The porosity of the bed when true fluidisation begins

The specific volume of air is expressed as the volume of: a. 1 kg of air at 101.325 kPa in cm3 b. 0.833 kg of air at standard pressure and temperature in m3 c. 1 kg of air at 101.325 kPa and 21 degrees Celsius in m3 d. 1 g of air occupied at any temperature and pressure e. 1 kg of air, regardless of temperature and pressure

Description : The specific volume of air is expressed as the volume of: a. 1 kg of air at 101.325 kPa in cm3 b. 0.833 kg of air at standard pressure and temperature in m3 c. 1 kg of air at 101.325 ... d. 1 g of air occupied at any temperature and pressure e. 1 kg of air, regardless of temperature and pressure

Last Answer : Answer: C

Pressure drop in a fluidised bed reactor is __________ that in a similar packed bed reactor. (A) Less than (B) Greater than (C) Same as (D) None of these

Description : Pressure drop in a fluidised bed reactor is __________ that in a similar packed bed reactor. (A) Less than (B) Greater than (C) Same as (D) None of these

Last Answer : (B) Greater than

. Which of the following is used as a catalyst in fluidised bed catalytic cracking? (A) Silica-magnesia (B) Silica-alumina (C) Bentonite clays (D) All (A), (B) and (C

Description : . Which of the following is used as a catalyst in fluidised bed catalytic cracking? (A) Silica-magnesia (B) Silica-alumina (C) Bentonite clays (D) All (A), (B) and (C

Last Answer : (D) All (A), (B) and (C

Oil is hydrogenated using nickel catalyst in a __________ reactor. (A) Batch (B) Slurry (C) Fluidised bed (D) Fixed bed

Description : Oil is hydrogenated using nickel catalyst in a __________ reactor. (A) Batch (B) Slurry (C) Fluidised bed (D) Fixed bed

Last Answer : (B) Slurry

Sub soilders are operated at maximum depth of (a) 30-40 cm (b) 45-75 cm (c) 75-90 cm (d) 10-20 cm

Description : Sub soilders are operated at maximum depth of (a) 30-40 cm (b) 45-75 cm (c) 75-90 cm (d) 10-20 cm

Last Answer : (b) 45-75 cm

A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 × 10 3 VOM + 10.94 × 10 6 V2 OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle ... fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s

Last Answer : (B) 16 mm/s

A mixture of 90 kg of rava and sugar contains 90% of sugar. The new mixture is formed by adding 30 kg of sugar. What is the percentage of sugar in the new mixture? a) 45 1/2 b) 60 1/5 c) 45 1/2 d) 92 1/2 e) 98 1/2

Description : A mixture of 90 kg of rava and sugar contains 90% of sugar. The new mixture is formed by adding 30 kg of sugar. What is the percentage of sugar in the new mixture? a) 45 1/2 b) 60 1/5 c) 45 1/2 d) 92 1/2 e) 98 1/2

Last Answer : Answer: D 90 kg = 81 kg sugar 9 kg rava Adding = 30 kg sugar Total = 111kg sugar 9kg rava (new)  111/120 × 100 = 92.5 =92 1 /2

BET apparatus is used to determine the (A) Specific surface of a porous catalyst (B) Pore size distribution (C) Pore diameter (D) Porosity of the catalyst bed

Description : BET apparatus is used to determine the (A) Specific surface of a porous catalyst (B) Pore size distribution (C) Pore diameter (D) Porosity of the catalyst bed

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Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates is not used to derive BET equation? (A) Langmuir's assumption applies to every adsorbed layer (B) There is no dynamic equilibrium between successive layer (C) The adsorbed layer may be polymolecular in thickness and the heat of adsorption in each layer (except the first one) is involved in each of the evaporation process (D) None of these

Description : Brunauer, Emmet and Teller (BET) equation is used to determine the specific surface area of a porous particle but not the pore volume & the porosity of the catalyst bed. Which of the following postulates ... (except the first one) is involved in each of the evaporation process (D) None of these

Last Answer : (B) There is no dynamic equilibrium between successive layer

Slugging in a fluidised bed can be avoided by using (A) Tall narrow vessel (B) Deep bed of solids (C) Shallow beds of solids and proper choice of particle size (D) Very large particles

Description : Slugging in a fluidised bed can be avoided by using (A) Tall narrow vessel (B) Deep bed of solids (C) Shallow beds of solids and proper choice of particle size (D) Very large particles

Last Answer : (C) Shallow beds of solids and proper choice of particle size

The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : The uniformity of a gas fluidised bed depends upon the __________ of the solid particles. (A) Size (B) Surface properties (C) Both (A) and (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) and (B)

In India, which one of the following should be considered the right combination of the age in days and live body weight in kg for a lamb for its weaning ? (A) 20 days to 30 days and 6 kg to 7 kg (B) 45 days to 60 days and 8 kg to 10 kg (C) 105 days to 120 days and 18 kg to 21 kg (D) 75 days to 90 days and 12 kg to 15 kg (E) 55 days to 70 days and 9 kg to 11 kg

Description : In India, which one of the following should be considered the right combination of the age in days and live body weight in kg for a lamb for its weaning ? (A) 20 days to 30 days and 6 kg to 7 kg (B) 45 days to 60 ... (D) 75 days to 90 days and 12 kg to 15 kg (E) 55 days to 70 days and 9 kg to 11 kg

Last Answer : (C) 105 days to 120 days and 18 kg to 21 kg

The live load to be considered for an accessible roof, is (A) Nil (B) 75 kg/m3 (C) 150 kg/m2 (D) 200 kg/cm

Description : The live load to be considered for an accessible roof, is (A) Nil (B) 75 kg/m3 (C) 150 kg/m2 (D) 200 kg/cm

Last Answer : Answer: Option C

An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively. The humidity of air sample expressed as kg of water vapour/kg of dry air is: (A) 0.048 (B) 0.079 (C) 0.122 (D) 0.152

Description : An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively ... air is: (A) 0.048 (B) 0.079 (C) 0.122 (D) 0.152

Last Answer : (D) 0.152

If is the angle of repose of soil of weight w kg/m3 , the horizontal pressure p at a depth of h metres per metre length of wall, is (A) wh × [(1 - sin )/(1 + )] (B) (wh/2) × [(1 - sin )/(1 + )] (C) wh - sin )/(1 + )] (D) wh )/(1 - )

Description : If is the angle of repose of soil of weight w kg/m3 , the horizontal pressure p at a depth of h metres per metre length of wall, is (A) wh × [(1 - sin )/(1 + )] (B) (wh/2) × [(1 - sin )/(1 + )] (C) wh - sin )/(1 + )] (D) wh )/(1 - )

Last Answer : Answer: Option A

Find the acceptance angle of a material which has a numerical aperture of 0.707 in air. a) 30 b) 60 c) 45 d) 90

Description : Find the acceptance angle of a material which has a numerical aperture of 0.707 in air. a) 30 b) 60 c) 45 d) 90

Last Answer : c) 45

Multistage operation (as in the case of catalytic oxidation of SO2 ) is not carried out for NH3 synthesis, because of (A) Comparatively higher pressure drop (B) High cost of the high pressure vessel used for the reactor (C) Higher pumping cost (D) Chances of entrainment and disturbance of catalyst bed

Description : Multistage operation (as in the case of catalytic oxidation of SO2 ) is not carried out for NH3 synthesis, because of (A) Comparatively higher pressure drop (B) High cost of the high pressure ... for the reactor (C) Higher pumping cost (D) Chances of entrainment and disturbance of catalyst bed

Last Answer : (B) High cost of the high pressure vessel used for the reactor

The pressure drop in a 30 cm diameter horizontal pipe is 60 kPa in distance of 15m. The wall shear stress in kPa is (a) 0.1 (b) 0.2 (c) 0.3 (d) 0.4

Description : The pressure drop in a 30 cm diameter horizontal pipe is 60 kPa in distance of 15m. The wall shear stress in kPa is (a) 0.1 (b) 0.2 (c) 0.3 (d) 0.4

Last Answer : (c) 0.3

Capacity of flight conveyor in tons/hr is given by (where, W & D = width and depth of flight respectively in metre V = speed of the conveyor, metre/second ρ = bulk density of material, kg/m3 ) (A) 3.6 W.D.V.ρ (B) 3.6 W.D.V (C) 3.6 W.V.ρ (D) 3.6 D.V.ρ

Description : Capacity of flight conveyor in tons/hr is given by (where, W & D = width and depth of flight respectively in metre V = speed of the conveyor, metre/second ρ = bulk density of material, kg/m3 ) (A) 3.6 W.D.V.ρ (B) 3.6 W.D.V (C) 3.6 W.V.ρ (D) 3.6 D.V.ρ

Last Answer : (A) 3.6 W.D.V.ρ

The angle at which the wave must be transmitted in air media if the angle of reflection is 45 degree is a) 45 b) 30 c) 60 d) 90

Description : The angle at which the wave must be transmitted in air media if the angle of reflection is 45 degree is a) 45 b) 30 c) 60 d) 90

Last Answer : a) 45

Injection pressure of fuel nozzle in diesel engine is a) 30-45 kg/cm2 b) 50-100 kg/cm2 c) 120-200 kg/cm2 d) 200 kg/cm2

Description : Injection pressure of fuel nozzle in diesel engine is a) 30-45 kg/cm2 b) 50-100 kg/cm2 c) 120-200 kg/cm2 d) 200 kg/cm2

Last Answer : c) 120-200 kg/cm2

For 100 sq. m cement concrete (1 : 2: 4) 4 cm thick floor, the quantity of cement required, is (A) 0.90 m3 (B) 0.94 m3 (C) 0.98 m3 (D) 1.00 m3

Description : For 100 sq. m cement concrete (1 : 2: 4) 4 cm thick floor, the quantity of cement required, is (A) 0.90 m3 (B) 0.94 m3 (C) 0.98 m3 (D) 1.00 m3

Last Answer : (B) 0.94 m3

Calorific value of pitch creosote mixture (PCM) i.e., C.T.F.-200 is about (A) 8800 kcal/m3 (B) 8800 kcal/kg (C) Same as that of coal middling (D) 25000 kcal/kg

Description : Calorific value of pitch creosote mixture (PCM) i.e., C.T.F.-200 is about (A) 8800 kcal/m3 (B) 8800 kcal/kg (C) Same as that of coal middling (D) 25000 kcal/kg

Last Answer : (B) 8800 kcal/kg

A 8 metre long simply supported rectangular beam which carries a distributed load 45 kg/m. experiences a maximum fibre stress 160 kg/cm2 . If the moment of inertia of the beam is 640 cm4 , the overall depth of the beam is (A) 10 cm (B) 12 cm (C) 15 cm (D) 18 cm

Description : A 8 metre long simply supported rectangular beam which carries a distributed load 45 kg/m. experiences a maximum fibre stress 160 kg/cm2 . If the moment of inertia of the beam is 640 cm4 , the overall depth of the beam is (A) 10 cm (B) 12 cm (C) 15 cm (D) 18 cm

Last Answer : (A) 10 cm

High strength of concrete requires a water cement ratio of [ A ] 0.10 to 0.15 [ B ] 0.25 to 0.30 [ C ] 0.45 to 0.60 [ D ] 0.75 to 0.90

Description : High strength of concrete requires a water cement ratio of [ A ] 0.10 to 0.15 [ B ] 0.25 to 0.30 [ C ] 0.45 to 0.60 [ D ] 0.75 to 0.90

Last Answer : [ B ] 0.25 to 0.30

Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor

Description : Which of the following is the most suitable for very high pressure gas phase reaction? (A) Batch reactor (B) Tubular flow reactor (C) Stirred tank reactor (D) Fluidised bed reactor

Last Answer : (B) Tubular flow reactor

In a single threaded worm and worm wheel the number of teeth on the worm wheel is 60. The diameter of the effort wheel is 12 cm and that of load drum is 8 cm. The velocity ratio will be a.90 b.120 c.60 d.45 e.107 dynes

Description : In a single threaded worm and worm wheel the number of teeth on the worm wheel is 60. The diameter of the effort wheel is 12 cm and that of load drum is 8 cm. The velocity ratio will be a.90 b.120 c.60 d.45 e.107 dynes

Last Answer : a. 90

In a single threaded worm and worm wheel the number of teeth on the worm wheel is 80. The diameter of the effort wheel is 12 cm and that of load drum is 8 cm. The velocity ratio will be a.60 b.45 c.120 d.107 dynes e.90

Description : In a single threaded worm and worm wheel the number of teeth on the worm wheel is 80. The diameter of the effort wheel is 12 cm and that of load drum is 8 cm. The velocity ratio will be a.60 b.45 c.120 d.107 dynes e.90

Last Answer : c. 120

A 30-m vertical column of fluid (density 1878 kg/m3 ) is located where g= 9.65 mps2 . Find the pressure at the base of the column. (Formula: pg= gρhg/k )  a. 543680 N/m2  b. 543.68 kPa (gauge)  c. Both a & b  d. None of the above

Description : A 30-m vertical column of fluid (density 1878 kg/m3 ) is located where g= 9.65 mps2 . Find the pressure at the base of the column. (Formula: pg= gρhg/k )  a. 543680 N/m2  b. 543.68 kPa (gauge)  c. Both a & b  d. None of the above

Last Answer : Both a & b

In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raffinate phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass of the extract phase is (in Kg) (A) 6.89 (B) 8.89 (C) 10 (D) 8.25

Description : In a single stage extraction process, 10 kg of pure solvent S (containing no solute A) is mixed with 30 kg of feed F containing A at a mass fraction xf = 0.2. The mixture splits into an extract phase E and a raffinate ... phase is (in Kg) (A) 6.89 (B) 8.89 (C) 10 (D) 8.25

Last Answer : (B) 8.89

A Pitot tube indicates 5 cm of water (manometer) when it is being used for measuring velocity of air. The velocity of air in m/sec is (A) 5 (B) 14.1 (C) 56.22 (D) 28.2

Description : A Pitot tube indicates 5 cm of water (manometer) when it is being used for measuring velocity of air. The velocity of air in m/sec is (A) 5 (B) 14.1 (C) 56.22 (D) 28.2

Last Answer : (D) 28.2

The mass of 2.5 m3 of a certain liquid is 2 tonnes. Its mass density is (A) 200 kg/m3 (B) 400 kg/m3 (C) 600 kg/m3 (D) 800 kg/m

Description : The mass of 2.5 m3 of a certain liquid is 2 tonnes. Its mass density is (A) 200 kg/m3 (B) 400 kg/m3 (C) 600 kg/m3 (D) 800 kg/m

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If the cohesive force (c), is 1.5 t/m2 , the density ) of the soil is 2.0 t/m3 , factor of safety (F) is 1.5 and stability factor (Sn) is 0.05, the safe height of a slope, is (A) 5 metres (B) 8 metres (C) 10 metres (D) 12 metres

Description : If the cohesive force (c), is 1.5 t/m2 , the density ) of the soil is 2.0 t/m3 , factor of safety (F) is 1.5 and stability factor (Sn) is 0.05, the safe height of a slope, is (A) 5 metres (B) 8 metres (C) 10 metres (D) 12 metres

Last Answer : (C) 10 metres

For a clay slope of height of 10 m, the stability number is 0.05, = 2.0 t/m3 , C = 2.5 t/m2 , the critical height of the slope of the soil, is (A) 4.0 m (B) 12.5 m (C) 25.0 m (D) 15.0 m

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Last Answer : (C) 25.0 m

At equilibrium the concentration of water in vapour phase (C* ) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room of air space 100m3 containing 2.2 kg of water vapour initially, 10 kg of dry silica gel is kept in the room. The fraction of initial water remaining in the air space after a long time (during which the temperature is maintained constant) is (A) 0.0 (B) 0.2 (C) 0.4 (D) 1.0

Description : At equilibrium the concentration of water in vapour phase (C* ) in kg/m3 of air space and the amount of water (m) adsorbed per kg of dry silica gel are related by, C* = 0.0667m. To maintain dry conditions in a room ... which the temperature is maintained constant) is (A) 0.0 (B) 0.2 (C) 0.4 (D) 1.0

Last Answer : (C) 0.4

If the atmospheric pressure on the surface of an oil tank (sp. gr. 0.8) is 0.2 kg/cm", the pressure at a depth of 50 m below the oil surface will be (A) 2 meters of water column (B) 3 meters of water column (C) 5 meters of water column (D) 6 meters of water Column

Description : If the atmospheric pressure on the surface of an oil tank (sp. gr. 0.8) is 0.2 kg/cm", the pressure at a depth of 50 m below the oil surface will be (A) 2 meters of water column (B) 3 meters of water column (C) 5 meters of water column (D) 6 meters of water Column

Last Answer : Answer: Option D

Filter aid is used to (A) Increase the rate of filtration (B) Decrease the pressure drop (C) Increase the porosity of the cake (D) Act as a support base for the septum

Description : Filter aid is used to (A) Increase the rate of filtration (B) Decrease the pressure drop (C) Increase the porosity of the cake (D) Act as a support base for the septum

Last Answer : (C) Increase the porosity of the cake

Half the angle of nip, (α), for a roll crusher is given by (where, dr, dp and df are diameters of crushing rolls, feed particles and rolls gap respectively). (A) cos α = (dr + dp)/(dr + df) (B) cos α = (dr + df)/(dr + dp) (C) tan α = (dr + dp)/(dr + df) (D) sin α = (dr + dp)/(dr + df)

Description : Half the angle of nip, (α), for a roll crusher is given by (where, dr, dp and df are diameters of crushing rolls, feed particles and rolls gap respectively). (A) cos α = (dr + dp)/(dr + df) (B) cos α = (dr + df)/(dr + dp) (C) tan α = (dr + dp)/(dr + df) (D) sin α = (dr + dp)/(dr + df)

Last Answer : (A) cos α = (dr + dp)/(dr + df)

The specific surface of spherical particles is proportional to (where, Dp = diameter of particle). (A) D2 p (B) Dp (C) 1/Dp (D) 1/D2p

Description : The specific surface of spherical particles is proportional to (where, Dp = diameter of particle). (A) D2 p (B) Dp (C) 1/Dp (D) 1/D2p

Last Answer : (C) 1/Dp

Offsets are measured with an accuracy of 1 in 40. If the point on the paper from both sources of error (due to angular and measurement errors) is not to exceed 0.05 cm on a scale of 1 cm = 20 m, the maximum length of offset should be limited to (A) 14.14 m (B) 28.28 m (C) 200 m (D) None of these

Description : Offsets are measured with an accuracy of 1 in 40. If the point on the paper from both sources of error (due to angular and measurement errors) is not to exceed 0.05 cm on a scale of 1 cm = 20 m, the maximum length of ... should be limited to (A) 14.14 m (B) 28.28 m (C) 200 m (D) None of these

Last Answer : (B) 28.28 m

According to IS: 456-2000, the maximum cement content exclusive of admixtures is [ A ] 200 kg/m3 [ B ] 300 kg/m3 [ C ] 450 kg/m3 [ D ] 550 kg/m3

Description : According to IS: 456-2000, the maximum cement content exclusive of admixtures is [ A ] 200 kg/m3 [ B ] 300 kg/m3 [ C ] 450 kg/m3 [ D ] 550 kg/m3

Last Answer : [ C ] 450 kg/m3

According to IS:456 minimum cement content inclusive of admixtures is [ A ] 200 kg/m3 [ B ] 300 kg/m3 [ C ] 450 kg/m3 [ D ] 550 kg/m3

Description : According to IS:456 minimum cement content inclusive of admixtures is [ A ] 200 kg/m3 [ B ] 300 kg/m3 [ C ] 450 kg/m3 [ D ] 550 kg/m3

Last Answer : [ B ] 300 kg/m3