Pick out the wrong statement. (A) Gape is the greatest distance between the crushing surfaces or the jaws (B) The angle of nip (2α) is the angle between roll faces at the level where they will just take hold of a particle and draw it in the crushing zone (C) Crushing efficiency is the ratio of the energy absorbed by the solid to the surfaces energy created by crushing (D) Reduction ratio is the ratio of the maximum size of the particles in the feed to that in the product

Pick out the wrong statement.
(A) Gape is the greatest distance between the crushing surfaces or the jaws
(B) The angle of nip (2α) is the angle between roll faces at the level where
they will just take hold of a particle and draw it in the crushing zone
(C) Crushing efficiency is the ratio of the energy absorbed by the solid to the
surfaces energy created by crushing
(D) Reduction ratio is the ratio of the maximum size of the particles in the
feed to that in the product
by

1 Answer

Answer :

(C) Crushing efficiency is the ratio of the energy absorbed by the solid to the
surfaces energy created by crushing
by

Related questions

Pick out the wrong statement pertaining to the roll crushers. (A) Maximum feed size determines the required roll diameter (B) For hard material's crushing, the reduction ratio should not exceed 4 (C) Both the rolls run necessarily at the same speed (D) Reduction ratio and differential roll speed affect production rate & energy consumed per unit of surface produced

Description : Pick out the wrong statement pertaining to the roll crushers. (A) Maximum feed size determines the required roll diameter (B) For hard material's crushing, the reduction ratio should not ... ratio and differential roll speed affect production rate & energy consumed per unit of surface produced

Last Answer : (C) Both the rolls run necessarily at the same speed

. Which of the following relationships between co-efficient of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct? (A) μ > tan α (B) μ ≥ tan α (C) μ > tan 2α (D) μ ≤ tan α

Description : . Which of the following relationships between co-efficient of friction (μ) between rock & roll and a (half of the angle of nip) of the particle to be crushed is correct? (A) μ > tan α (B) μ ≥ tan α (C) μ > tan 2α (D) μ ≤ tan α

Last Answer : (B) μ ≥ tan α

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)

Bond crushing law (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law (B) Is less realistic in estimating the power requirements of commercial crushers (C) States that the work required to form particle of any size from very large feed is proportional to the square root of the volume to surface ratio of the product (D) States that the work required for the crushing is proportional to the new surface created

Description : Bond crushing law (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law (B) Is less realistic in estimating the power requirements of commercial crushers ( ... (D) States that the work required for the crushing is proportional to the new surface created

Last Answer : (A) Calls for relatively less energy for the smaller product particles, than does the Rittinger law

Pick out the wrong statement: (A) Magnetic separation method can be employed to treat both dry & wet ores (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed size to the maximum product size (C) Gyratory crusher is used for coarse crushing (D) Screens are of stationary, moving and vibratory types

Description : Pick out the wrong statement: (A) Magnetic separation method can be employed to treat both dry & wet ores (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed ... ) Gyratory crusher is used for coarse crushing (D) Screens are of stationary, moving and vibratory types

Last Answer : (B) Reduction ratio in crushing operation is defined as the ratio of minimum feed size to the maximum product size

Rittinger's crushing law states that (A) Work required to form a particle of any size is proportional to the square of the surface to volume ratio of the product (B) Work required to form a particle of a particular size is proportional to the square root of the surface to volume ratio of the product (C) Work required in crushing is proportional to the new surface created (D) For a given machine and feed, crushing efficiency is dependent on the size of the feed & product

Description : Rittinger's crushing law states that (A) Work required to form a particle of any size is proportional to the square of the surface to volume ratio of the product (B) Work required to form a ... ) For a given machine and feed, crushing efficiency is dependent on the size of the feed & product

Last Answer : (C) Work required in crushing is proportional to the new surface created

Angle of nip of the crushing rolls does not depend upon the (A) Diameter of the rolls (B) Speed of the rolls (C) Product size (D) Feed size

Description : Angle of nip of the crushing rolls does not depend upon the (A) Diameter of the rolls (B) Speed of the rolls (C) Product size (D) Feed size

Last Answer : (B) Speed of the rolls

Crushing efficiency is the ratio of the (A) Surface energy created by crushing to the energy absorbed by the solid (B) Energy absorbed by the solid to that fed to the machine (C) Energy fed to the machine to the surface energy created by crushing (D) Energy absorbed by the solid to the surface energy created by crushing

Description : Crushing efficiency is the ratio of the (A) Surface energy created by crushing to the energy absorbed by the solid (B) Energy absorbed by the solid to that fed to the machine (C) Energy ... surface energy created by crushing (D) Energy absorbed by the solid to the surface energy created by crushing

Last Answer : (A) Surface energy created by crushing to the energy absorbed by the solid

In case of a hammer crusher, (A) Crushing takes place by impact breaking (B) Maximum acceptable feed size is 30 cms (C) Reduction ratio can be varied by adjusting the distance from cage to hammers (D) All (A), (B) and (C)

Description : In case of a hammer crusher, (A) Crushing takes place by impact breaking (B) Maximum acceptable feed size is 30 cms (C) Reduction ratio can be varied by adjusting the distance from cage to hammers (D) All (A), (B) and (C)

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

Energy consumption in a crusher decreases with increase in the (A) Size of the product (at constant feed size) (B) Capacity of the crushing machine (C) Size of feed (at constant reduction ratio) (D) All (A), (B) & (C)

Description : Energy consumption in a crusher decreases with increase in the (A) Size of the product (at constant feed size) (B) Capacity of the crushing machine (C) Size of feed (at constant reduction ratio) (D) All (A), (B) & (C)

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

According to Bond crushing law, the work required to form particle of size 'D' from very large feed is (where (S/V)p and (S/V) f are surface to volume ratio of the product and feed respectively). (A) (S/V)p (B) √(S/V)p (C) (S/V) 2 p (D) (S/V) f

Description : According to Bond crushing law, the work required to form particle of size 'D' from very large feed is (where (S/V)p and (S/V) f are surface to volume ratio of the product and feed respectively). (A) (S/V)p (B) √(S/V)p (C) (S/V) 2 p (D) (S/V) f

Last Answer : (B) √(S/V)

Pick out the wrong statement. (A) Recycled coarse material to the grinder by a classifier is termed as circulating load (B) Wear and tear in wet crushing is more than that in dry crushing of materials (C) Size enlargement (opposite of size reduction) is not a mechanical operation (D) A 'dust catcher' is simply an enlargement in a pipeline which permits the solids to settle down due to reduction in velocity of the dust laden gas

Description : Pick out the wrong statement. (A) Recycled coarse material to the grinder by a classifier is termed as circulating load (B) Wear and tear in wet crushing is more than that in dry crushing of ... a pipeline which permits the solids to settle down due to reduction in velocity of the dust laden gas

Last Answer : (C) Size enlargement (opposite of size reduction) is not a mechanical operation

What is the usual value of angle of nip for crushing of ordinary rock in smooth steel crushing rolls? (A) 16° (B) 32° (C) 40° (D) 46°

Description : What is the usual value of angle of nip for crushing of ordinary rock in smooth steel crushing rolls? (A) 16° (B) 32° (C) 40° (D) 46°

Last Answer : (B) 32°

The capacity of a gyratory crusher is __________ that of a jaw crusher with the same gape, handling the same feed & for the same product size range. (A) Same as (B) 2.5 times (C) 5 times (D) 10 times

Description : The capacity of a gyratory crusher is __________ that of a jaw crusher with the same gape, handling the same feed & for the same product size range. (A) Same as (B) 2.5 times (C) 5 times (D) 10 times

Last Answer : (B) 2.5 times

For crushing of solids, the Rittinger's law states that the work required for crushing is proportional to(A) The new surface created(B) The size reduction ratio(C) The change in volume due to crushing(D) None of these

Description : For crushing of solids, the Rittinger's law states that the work required for crushing is proportional to (A) The new surface created (B) The size reduction ratio (C) The change in volume due to crushing (D) None of these

Last Answer : (A) The new surface created

In a size reduction crushing operation, the feed size is 10 to 50 mm, while the product size is 2 to 10 mm. This is a case of __________ crushing. (A) Primary (B) Secondary (C) Fine

Description : In a size reduction crushing operation, the feed size is 10 to 50 mm, while the product size is 2 to 10 mm. This is a case of __________ crushing. (A) Primary (B) Secondary (C) Fine

Last Answer : (C) Fine

In a size reduction crushing operation, feed size is 100 to 300 mm. while the product size is 10 to 50 mm. This is a case of the __________ crushing. (A) Primary (B) Secondary (C) Fine (D) Ultrafine

Description : In a size reduction crushing operation, feed size is 100 to 300 mm. while the product size is 10 to 50 mm. This is a case of the __________ crushing. (A) Primary (B) Secondary (C) Fine (D) Ultrafine

Last Answer : (B) Secondary

In a size reduction crushing operation, feed size is 300 to 1500 mm while the product size is 100 to 300 mm. This is a case of the __________ crushing. (A) Secondary (B) Fine (C) Primary (D) Ultrafine

Description : In a size reduction crushing operation, feed size is 300 to 1500 mm while the product size is 100 to 300 mm. This is a case of the __________ crushing. (A) Secondary (B) Fine (C) Primary (D) Ultrafine

Last Answer : (C) Primary

The term 'angle of nip' is concerned with the operation of the __________ crushers. (A) Jaw (B) Roll (C) Gyratory (D) None of these

Description : The term 'angle of nip' is concerned with the operation of the __________ crushers. (A) Jaw (B) Roll (C) Gyratory (D) None of these

Last Answer : (B) Roll

Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In small columns, local efficiency is larger than Murphree efficiency; in large columns local efficiency is smaller than Murphree efficiency (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s (D) The concentration and hydrodynamic boundary layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Description : Pick out the wrong statement. (A) In the McCabe-Thiele diagram for binary distillation, vertical feed line represents saturated liquid feed and horizontal feed line represents saturated vapour feed (B) In ... layers over a flat plate are of equal thickness, if Schmidt number is equal to unity

Last Answer : (C) For Laminar flow over a plate of length L, the local mass transfer co￾efficient at a distance L from the leading edge is 1.5 × 10 -2m/s. Then the average mass transfer co-efficient for the plate is 2 × 10 -2m/s

Which of the following achieves the least reduction ratio for a given feed size? (A) Jaw crusher (B) Roll crusher (C) Cone crusher (D) Gyratory crusher

Description : Which of the following achieves the least reduction ratio for a given feed size? (A) Jaw crusher (B) Roll crusher (C) Cone crusher (D) Gyratory crusher

Last Answer : (B) Roll crusher

Pick out the correct statement. (A) Plastic chips are called non-cohesive solids (B) Kick's crushing law is, P/m = K . ln (D̅sa /Ds̅b ) (C) Communition is a generic term for size enlargement operation (D) Energy required in kwh per ton of product, such that 80% of it passes through a 200 mesh screen, is called 'Work index'

Description : Pick out the correct statement. (A) Plastic chips are called non-cohesive solids (B) Kick's crushing law is, P/m = K . ln (D̅sa /Ds̅b ) (C) Communition is a generic term for size enlargement ... per ton of product, such that 80% of it passes through a 200 mesh screen, is called 'Work index'

Last Answer : (B) Kick's crushing law is, P/m = K . ln (D̅sa /Ds̅b )

Crushing of mineral particles is accomplished in a 'cage mill', when one or more alloy steel bars are revolved in opposite directions. It is a type of __________ mill. (A) Impact (B) Roll (C) Vibratory (D) None of these

Description : Crushing of mineral particles is accomplished in a 'cage mill', when one or more alloy steel bars are revolved in opposite directions. It is a type of __________ mill. (A) Impact (B) Roll (C) Vibratory (D) None of these

Last Answer : (A) Impact

Austenitic manganese steel used for making jaws of crushing machines contains about __________ percent manganese. (A) 1.5-2 (B) 3.5-4.5 (C) 7-9 (D) 12-14

Description : Austenitic manganese steel used for making jaws of crushing machines contains about __________ percent manganese. (A) 1.5-2 (B) 3.5-4.5 (C) 7-9 (D) 12-14

Last Answer : (D) 12-14

Pick out the wrong statement (A) The concentric atmosphere layer just above troposphere is called stratosphere, which is rich in ozone (B) Mesosphere is characterised by very low atmospheric pressure and low temperature (C) Troposphere is a dusty zone containing water vapor and clouds (D) The radio waves used in the long distance radio communication are reflected back to earth by stratosphere

Description : Pick out the wrong statement (A) The concentric atmosphere layer just above troposphere is called stratosphere, which is rich in ozone (B) Mesosphere is characterised by very low atmospheric ... radio waves used in the long distance radio communication are reflected back to earth by stratosphere

Last Answer : (D) The radio waves used in the long distance radio communication are reflected back to earth by stratosphere

Pick out the wrong statement. (A) Nitrogen is normally supplied in fertiliser either in Ammoniacal or the nitrate form, from which the soil takes it up in the form of ammonium ions ornitrate ions and forms amino acids(B) Calcium present in the fertiliser helps in correcting the soil acidity(C) Particle size range of a good granular fertiliser is 10-15 mesh and itcontains less moisture as compared to finely divided powder form of fertiliser(D) Ammonium nitrate fertiliser is obtained as a by-product in an integratedsteel plant having by-product coke ovens

Description : Pick out the wrong statement. (A) Nitrogen is normally supplied in fertiliser either in Ammoniacal or the nitrate form, from which the soil takes it up in the form of ammonium ions ornitrate ... nitrate fertiliser is obtained as a by-product in an integrated steel plant having by-product coke ovens

Last Answer : (D) Ammonium nitrate fertiliser is obtained as a by-product in an integrated steel plant having by-product coke ovens

Solid angle subtended by the finite surface at the radiating element is (A) Called the view factor (B) Called the angle of vision (C) Proportional to the square of the distance between surfaces (D) Expressed in terms of radians

Description : Solid angle subtended by the finite surface at the radiating element is (A) Called the view factor (B) Called the angle of vision (C) Proportional to the square of the distance between surfaces (D) Expressed in terms of radians

Last Answer : (B) Called the angle of vision

During size reduction by a jaw crusher, the energy consumed decreases with the (A) Decreasing size of product at constant size of feed (B) Decreasing machine capacity (C) Increasing size of feed at constant reduction ratio (D) None of these

Description : During size reduction by a jaw crusher, the energy consumed decreases with the (A) Decreasing size of product at constant size of feed (B) Decreasing machine capacity (C) Increasing size of feed at constant reduction ratio (D) None of these

Last Answer : (C) Increasing size of feed at constant reduction ratio

Pick out the wrong statement. (A) Atoms with same number of nucleons but different number of protons are called isobars (B) Atoms with same number of protons but different number of nucleons are called isoters (C) Out of α, β, and γ-rays, the one having maximum penetration power are γ-rays (D) The product formed by emission of α-particle has mass number less by 4 units than the parent nuclide

Description : Pick out the wrong statement. (A) Atoms with same number of nucleons but different number of protons are called isobars (B) Atoms with same number of protons but different number of nucleons are ... product formed by emission of α-particle has mass number less by 4 units than the parent nuclide

Last Answer : (B) Atoms with same number of protons but different number of nucleons are called isoters

Pick out the wrong statement. (A) The ratio of the density of the 'nucleus' to that of the 'atom' is 10 12 (B) α-particle is identical with a doubly charged helium ion (C) The mass of deuterium atom is half that of helium atom (D) Gamma rays are high energy electrons

Description : Pick out the wrong statement. (A) The ratio of the density of the 'nucleus' to that of the 'atom' is 10 12 (B) α-particle is identical with a doubly charged helium ion (C) The mass of deuterium atom is half that of helium atom (D) Gamma rays are high energy electrons

Last Answer : (D) Gamma rays are high energy electrons

Pick out the wrong statement. (A) The binary diffusivity in liquids is of the order of 10 -5 cm2 /sec (B) Molecular diffusion in solid is much faster than that in liquids (C) Particles movement from higher concentration to lower concentration takes place in diffusion process (D) According to Poiseuille's law, the permeability decreases with increase in temperature for flow of a gas through a given capillary

Description : Pick out the wrong statement. (A) The binary diffusivity in liquids is of the order of 10 -5 cm2 /sec (B) Molecular diffusion in solid is much faster than that in liquids ( ... Poiseuille's law, the permeability decreases with increase in temperature for flow of a gas through a given capillary

Last Answer : (B) Molecular diffusion in solid is much faster than that in liquids

Pick out the wrong statement. (A) Angle of repose of coal increases with its increasing size (B) Specific gravity of coal increases with its increasing maturity (C) Refractive index and reflectance of coal increases with the increasing rank of coal (D) Specific heat of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal

Description : Pick out the wrong statement. (A) Angle of repose of coal increases with its increasing size (B) Specific gravity of coal increases with its increasing maturity (C) Refractive index and reflectance of ... of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal

Last Answer : (D) Specific heat of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal

The mechanism of size reduction by a hammer mill is by impact and attrition between the (A) Grinding element & the housing (B) Feed particles (C) Both (A) and (B) (D) Neither (A) nor (B)

Description : The mechanism of size reduction by a hammer mill is by impact and attrition between the (A) Grinding element & the housing (B) Feed particles (C) Both (A) and (B) (D) Neither (A) nor (B)

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

Character which is closely related to human evolution is (a) disappearance of tail (b) reduction in size of jaws (c) binocular vision (d) flat nails

Description : Character which is closely related to human evolution is (a) disappearance of tail (b) reduction in size of jaws (c) binocular vision (d) flat nails

Last Answer : a) disappearance of tail

Pick out the wrong statement. (A) For the compressible cake, voidage & the specific resistance of the cake can be assumed to be constant (B) Cake resistance is independent of the pressure drop (C) Crushing of explosive materials are done by employing dry-grinding (D) Gyratory crusher is a coarse crusher

Description : Pick out the wrong statement. (A) For the compressible cake, voidage & the specific resistance of the cake can be assumed to be constant (B) Cake resistance is independent of the pressure ... Crushing of explosive materials are done by employing dry-grinding (D) Gyratory crusher is a coarse crusher

Last Answer : (B) Cake resistance is independent of the pressure drop

Pick out the wrong statement. (A) The equivalent stiffness of two springs (of equal stiffness 'S') in series is S/2 while in parallel is 2S (B) For a helical spring, deflection is proportional to D3(D = mean coil diameter) or d4(d = wire diameter) (C) Crushing load or columns is less than the buckling load (D) Modulus of resilience is proportional to (stress at elastic limit)2

Description : Pick out the wrong statement. (A) The equivalent stiffness of two springs (of equal stiffness 'S') in series is S/2 while in parallel is 2S (B) For a helical spring, deflection is ... is less than the buckling load (D) Modulus of resilience is proportional to (stress at elastic limit)2

Last Answer : (C) Crushing load or columns is less than the buckling load

A leaf spring consists of 3 extra full length leaves and 14 graduated length leaves. The maximum force that can act on the spring is 70kN and the distance between eyes of the spring is 1.2m. Width and thickness of the leaves are 100mm and 12mm respectively. Calculate the initial pre load required to close the nip. (a) 4332.2N (b) 4674.1N (c) 4985.4N (d) Can’t be determined

Description : A leaf spring consists of 3 extra full length leaves and 14 graduated length leaves. The maximum force that can act on the spring is 70kN and the distance between eyes of the spring is 1.2m. Width and thickness of the ... close the nip. (a) 4332.2N (b) 4674.1N (c) 4985.4N (d) Can't be determined

Last Answer : (b) 4674.1N

A leaf spring consists of 3 extra full length leaves and 14 graduated length leaves. The maximum force that can act on the spring is 70kN and the distance between eyes of the spring is 1.2m. Width and thickness of the leaves are 100mm and 12mm respectively. If modulus of elasticity is 207000N/mm², calculate the initial nip. (a) 26.8mm (b) 24.9mm (c) 22.5mm (d)23.1mm

Description : A leaf spring consists of 3 extra full length leaves and 14 graduated length leaves. The maximum force that can act on the spring is 70kN and the distance between eyes of the spring is 1.2m. Width and thickness of the ... /mm², calculate the initial nip. (a) 26.8mm (b) 24.9mm (c) 22.5mm (d)23.1mm

Last Answer : b) 24.9mm

When primary molars are prepared for stainless steel crowns, should the depth for reduction of the proximal surface be similar to the depth of the buccal and lingual surfaces? A. Yes; reduction of all wall is similar for best retention B. No, proximal reduction is greater to allow the crown to pass the contact area C. No, the buccal surfaces has the greatest reduction to remove the cervical bulge D. Yes, all undercuts are uniformly removed so that the steel crown can be seated E. No, because of lateral constriction, the lingual surface needs greatest reduction

Description : When primary molars are prepared for stainless steel crowns, should the depth for reduction of the proximal surface be similar to the depth of the buccal and lingual surfaces? A. Yes; reduction ... can be seated E. No, because of lateral constriction, the lingual surface needs greatest reduction

Last Answer : B. No, proximal reduction is greater to allow the crown to pass the contact area

Pick out the wrong statement. (A) Heat transfer from a hot body to cold body by the emission of heat waves is called radiation (B) Filmwise condensation takes place on non-wettable surfaces (C) The boiling point of a solution is affected by liquid head as well as boiling point elevation (D) None of these

Description : Pick out the wrong statement. (A) Heat transfer from a hot body to cold body by the emission of heat waves is called radiation (B) Filmwise condensation takes place on non-wettable surfaces (C) The ... of a solution is affected by liquid head as well as boiling point elevation (D) None of these

Last Answer : (B) Filmwise condensation takes place on non-wettable surfaces

Work index is the gross energy (kWh/tonne of feed) necessary to reduce a very large feed to such a size that 80% of product particles will pass through a 0.1 mm screen. The value of work index determined for wet grinding should be multiplied with __________ to get the same for dry grinding. (A) 1.0 (B) 0.5 (C) 1.34 (D) 4.34

Description : Work index is the gross energy (kWh/tonne of feed) necessary to reduce a very large feed to such a size that 80% of product particles will pass through a 0.1 mm screen. The value of work index determined for wet grinding should ... to get the same for dry grinding. (A) 1.0 (B) 0.5 (C) 1.34 (D) 4.34

Last Answer : (C) 1.34

Pick out the wrong statement. (A) More commonly used jaw crusher between Dodge jaw crusher and Blake jaw crusher is the later one(B) There are only four methods namely compression, impact, attrition andcutting, which the size reduction equipments employ(C) Cutting machines mainly employ 'attrition' for size reduction of solids(D) Operating principles of Dodge and Blake jaw crushers are combined inthe working of universal jaw crushers

Description : Pick out the wrong statement. (A) More commonly used jaw crusher between Dodge jaw crusher and Blake jaw crusher is the later one (B) There are only four methods namely compression, impact ... Operating principles of Dodge and Blake jaw crushers are combined in the working of universal jaw crushers

Last Answer : (C) Cutting machines mainly employ 'attrition' for size reduction of solids

Pick out the wrong statement. (A) With decrease in feed temperature, the number of plates required for binary distillation decreases for a given ‘L/V’ ratio (B) The extraction per unit of total height for a short packed column is more effective than for a tall column, in case of liquid-liquid extraction(C) Natural draft cooling towers are made of ferroconcrete and its cross￾section is wider at the bottom(D) Vander wall adsorption is also called chemisorption

Description : Pick out the wrong statement. (A) With decrease in feed temperature, the number of plates required for binary distillation decreases for a given L/V' ratio (B) The extraction per unit ... and its cross￾section is wider at the bottom (D) Vander wall adsorption is also called chemisorption

Last Answer : (D) Vander wall adsorption is also called chemisorption

Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate or larger amounts of data (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order (D) The ratio of volumes of plug flow reactor to that of mixed reactor is always less than one for identical feed composition, flow rate, conversion and for all positive reaction orders

Description : Pick out the wrong statement. (A) The integral method of analysing kinetic data is used when the data is scattered (B) The differential method of analysing kinetic data requires more accurate ... less than one for identical feed composition, flow rate, conversion and for all positive reaction orders

Last Answer : (C) When the reaction rate is independent of temperature, the reaction is said to be of zero order

Rittinger number which designates the new surface produced per unit of mechanical energy absorbed by the material being crushed, depends on the (A) State or manner of application of the crushing force (B) Ultimate strength of the material (C) Elastic constant of the material (D) All (A), (B) and (C)

Description : Rittinger number which designates the new surface produced per unit of mechanical energy absorbed by the material being crushed, depends on the (A) State or manner of application of the crushing force (B) Ultimate strength of the material (C) Elastic constant of the material (D) All (A), (B) and (C)

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

Pick out the wrong statement. (A) Trouton's ratio of non-polar liquids is calculated using Kistyakowsky equation (B) Thermal efficiency of a Carnot engine is always less than 1 (C) An equation relating pressure, volume and temperature of a gas is called ideal gas equation (D) None of these

Description : Pick out the wrong statement. (A) Trouton's ratio of non-polar liquids is calculated using Kistyakowsky equation (B) Thermal efficiency of a Carnot engine is always less than 1 (C) An equation relating pressure, volume and temperature of a gas is called ideal gas equation (D) None of these

Last Answer : (C) An equation relating pressure, volume and temperature of a gas is called ideal gas equation