Particles having diameter greater than 75 μm (micrometer = 10 -6 mm) are called (A) Grit (B) Dust (C) Powder (D) Smoke

Particles having diameter greater than 75 μm (micrometer = 10
-6 mm)
are called
(A) Grit
(B) Dust
(C) Powder
(D) Smoke
by

1 Answer

Answer :

(A) Grit
by

Related questions

Carbonaceous particles having size less than 1 μm are called (A) Grit (B) Aggregates (C) Aerosols (D) Smoke

Description : Carbonaceous particles having size less than 1 μm are called (A) Grit (B) Aggregates (C) Aerosols (D) Smoke

Last Answer : (D) Smoke

5-200 μm size particles are called (A) Colloids or aerosols (B) Powder (C) Dust (D) Smoke

Description : 5-200 μm size particles are called (A) Colloids or aerosols (B) Powder (C) Dust (D) Smoke

Last Answer : (A) Colloids or aerosols

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

80% less than 200 mesh size particles are called (A) Smoke (B) Powder (C) Grit (D) Aggregates

Description : 80% less than 200 mesh size particles are called (A) Smoke (B) Powder (C) Grit (D) Aggregates

Last Answer : (B) Powder

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

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 system ... What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8

Last Answer : (C) 0.7

The energy required per unit mass to grind limestone particles of very large size to 100 μm is 12.7 kWh/ton. An estimate (using Bond's law) of the energy to grind the particles from a very large size to 50 μm is (A) 6.35 kWh/ton (B) 9.0 kWh/ton (C) 18 kWh/ton (D) 25.4 kWh/ton

Description : The energy required per unit mass to grind limestone particles of very large size to 100 μm is 12.7 kWh/ton. An estimate (using Bond's law) of the energy to grind the particles from a very large size to 50 μm is (A) 6.35 kWh/ton (B) 9.0 kWh/ton (C) 18 kWh/ton (D) 25.4 kWh/ton

Last Answer : (C) 18 kWh/ton

Combustion of pulverised fuel (A) Requires larger combustion chamber than rich gaseous fuel (B) In a metallurgical furnace does not contaminate the product in the furnace by ash from fuel (C) Suppresses the discharge of fine dust and grit into atmosphere (D) All (A), (B) and (C)

Description : Combustion of pulverised fuel (A) Requires larger combustion chamber than rich gaseous fuel (B) In a metallurgical furnace does not contaminate the product in the furnace by ash from fuel (C) Suppresses the discharge of fine dust and grit into atmosphere (D) All (A), (B) and (C)

Last Answer : (A) Requires larger combustion chamber than rich gaseous fuel

Hazen’s formula VS = 418 (GS – Gw)d [(3T + 70)/100] is used for the settlement velocity of the particles of diameter A. Less than 0.01 mm B. Less than 0.05 mm C. Less than 0.1 mm D. Greater than 0.1 mm

Description : Hazen’s formula VS = 418 (GS – Gw)d [(3T + 70)/100] is used for the settlement velocity of the particles of diameter A. Less than 0.01 mm B. Less than 0.05 mm C. Less than 0.1 mm D. Greater than 0.1 mm

Last Answer : ANS: D

A 30% (by volume) suspension of spherical sand particles in a viscous oil has a hindered settling velocity of 4.44 μm/s. If the Richardson Zaki hindered settling index is 4.5, then the terminal velocity of a sand grain is (A) 0.90 μm/s (B) 1 μm/s (C) 22.1 μm/s (D) 0.02 μm/s

Description : A 30% (by volume) suspension of spherical sand particles in a viscous oil has a hindered settling velocity of 4.44 μm/s. If the Richardson Zaki hindered settling index is 4.5, then the terminal velocity of a sand grain is (A) 0.90 μm/s (B) 1 μm/s (C) 22.1 μm/s (D) 0.02 μm/s

Last Answer : (B) 1 μm/s

Oxygen molecule absorption peaks to electromagnetic wave are at what wavelengths? A. 1.35 cm and 1.7 mm B. 5 mm and 2.5 mm C. 5 cm and 2.5 cm D. 1.35 mm and 1.7 μm

Description : Oxygen molecule absorption peaks to electromagnetic wave are at what wavelengths? A. 1.35 cm and 1.7 mm B. 5 mm and 2.5 mm C. 5 cm and 2.5 cm D. 1.35 mm and 1.7 μm

Last Answer : B. 5 mm and 2.5 mm

Oxygen molecule absorption peaks to electromagnetic wave are at what wavelengths? A. 1.35 mm and 1.7 μm B. 1.35 cm and 1.7 mm C. 5 cm and 2.5 cm D. 5 mm and 2.5 mm

Description : Oxygen molecule absorption peaks to electromagnetic wave are at what wavelengths? A. 1.35 mm and 1.7 μm B. 1.35 cm and 1.7 mm C. 5 cm and 2.5 cm D. 5 mm and 2.5 mm

Last Answer : D. 5 mm and 2.5 mm

Pick up the correct statement from the following: (A) The maximum size of a coarse aggregate, is 75 mm and minimum 4.75 mm (B) The maximum size of the fine aggregate, is 4.75 mm and minimum 0.075 mm (C) The material having particles of size varying from 0.06 mm to 0.002 mm, is known as silt (D) All the ab

Description : Pick up the correct statement from the following: (A) The maximum size of a coarse aggregate, is 75 mm and minimum 4.75 mm (B) The maximum size of the fine aggregate, is 4.75 mm and minimum 0.075 mm ( ... having particles of size varying from 0.06 mm to 0.002 mm, is known as silt (D) All the ab

Last Answer : Answer: Option D

A reinforced concrete slab is 75 mm thick. The maximum size of reinforcement bar that can be used is (a) 6 mm diameter (b) 8 mm diameter (c) 10 mm diameter (d) 12 mm diameter

Description : A reinforced concrete slab is 75 mm thick. The maximum size of reinforcement bar that can be used is (a) 6 mm diameter (b) 8 mm diameter (c) 10 mm diameter (d) 12 mm diameter

Last Answer : (b) 8 mm diameter

For achieving rapid drying rate in a spray dryer, the diameter of the particles in the feed should be in the range of __________ microns (1 mm = 1000 microns). (A) 1-5 (B) 10-60 (C) 200-300

Description : For achieving rapid drying rate in a spray dryer, the diameter of the particles in the feed should be in the range of __________ microns (1 mm = 1000 microns). (A) 1-5 (B) 10-60 (C) 200-300

Last Answer : (B) 10-60

The settlement velocity of a solid (diameter 0.5 mm, specific gravity 1.75) in water having temperature 10°C, is A. 213.5 cm/sec B. 313.5 cm/sec C. 413.5 cm/sec D. 500 cm/sec

Description : The settlement velocity of a solid (diameter 0.5 mm, specific gravity 1.75) in water having temperature 10°C, is A. 213.5 cm/sec B. 313.5 cm/sec C. 413.5 cm/sec D. 500 cm/sec

Last Answer : ANS: B

Most appropriate instrument for measurement of internal and external diameter of a tube is A. vernier callipers B. micrometer screw gauge C. meter rule D. measuring tape

Description : Most appropriate instrument for measurement of internal and external diameter of a tube is A. vernier callipers B. micrometer screw gauge C. meter rule D. measuring tape

Last Answer : vernier callipers

Single-mode step-index cable has a core diameter in the range of ∙ A. 100 to 1000 micrometer ∙ B. 50 to 100 micrometer ∙ C. 2 to 15 micrometer ∙ D. 5 to 20 micrometer

Description : Single-mode step-index cable has a core diameter in the range of ∙ A. 100 to 1000 micrometer ∙ B. 50 to 100 micrometer ∙ C. 2 to 15 micrometer ∙ D. 5 to 20 micrometer

Last Answer : . 2 to 15 micrometer

Smoke point of a good burning kerosene may be around __________ mm. (A) 0-5 (B) 20-25 (C) 60-75 (D) 100-120

Description : Smoke point of a good burning kerosene may be around __________ mm. (A) 0-5 (B) 20-25 (C) 60-75 (D) 100-120

Last Answer : (B) 20-25

If a grading curve is horizontal between the portions of 20 mm I.S. Sieve and 4.75 mm I.S. Sieve, the graded aggregates do not contain (A) 20 mm particles (B) 10 mm particles (C) 4.75 mm particles (D) All the above

Description : If a grading curve is horizontal between the portions of 20 mm I.S. Sieve and 4.75 mm I.S. Sieve, the graded aggregates do not contain (A) 20 mm particles (B) 10 mm particles (C) 4.75 mm particles (D) All the above

Last Answer : Answer: Option D

A circular pipe is subjected to maximum shear force of 60 kN. What is the diameter of the pipe if maximum allowable shear stress is 5 Mpa? a. 27.311 mm b. 75.56 mm c. 142.72 mm d. 692.10 mm

Description : A circular pipe is subjected to maximum shear force of 60 kN. What is the diameter of the pipe if maximum allowable shear stress is 5 Mpa? a. 27.311 mm b. 75.56 mm c. 142.72 mm d. 692.10 mm

Last Answer : c. 142.72 mm

According to IS classification, the range of silt size particles is (A) 4.75 mm to 2.00 mm (B) 2.00 mm to 0.425 mm (C) 0.425 mm to 0.075 mm (D) 0.075 mm to 0.002 mm

Description : According to IS classification, the range of silt size particles is (A) 4.75 mm to 2.00 mm (B) 2.00 mm to 0.425 mm (C) 0.425 mm to 0.075 mm (D) 0.075 mm to 0.002 mm

Last Answer : (D) 0.075 mm to 0.002 mm

The diameter of very fine sand particles is- (a) Below 0.002 mm (b) 0.05-0.002mm (c) 0.01-0.05 mm (d) 0.05-0.10mm

Description : The diameter of very fine sand particles is- (a) Below 0.002 mm (b) 0.05-0.002mm (c) 0.01-0.05 mm (d) 0.05-0.10mm

Last Answer : (c) 0.01-0.05 mm

What is the characteristic impedance of a single wire with a diameter d= 0.25 mm placed at the center between grounded parallel planes separated by 1 mm apart. The wire is held by a material with a velocity factor of 0.75. A. 85 Ω B. 63 Ω C. 50 Ω D. 75 Ω

Description : What is the characteristic impedance of a single wire with a diameter d= 0.25 mm placed at the center between grounded parallel planes separated by 1 mm apart. The wire is held by a material with a velocity factor of 0.75. A. 85 Ω B. 63 Ω C. 50 Ω D. 75 Ω

Last Answer : D. 75 Ω

A solid shaft has diameter 80 mm. It is subjected to a torque of 4 KNm. The maximum shear stress induced in the shaft would be (a) 75/p N/mm2 (b) 250/p N/mm2 (c) 125/p N/mm2 (d) 150/p N/mm2

Description : A solid shaft has diameter 80 mm. It is subjected to a torque of 4 KNm. The maximum shear stress induced in the shaft would be (a) 75/p N/mm2 (b) 250/p N/mm2 (c) 125/p N/mm2 (d) 150/p N/mm2

Last Answer : (c) 125/p N/mm2

Calculate the static deflection in μm of transverse vibrations if the frequency is 200Hz. A. 6.21 B. 0.621 C. 62.1 D. 0.006

Description : Calculate the static deflection in μm of transverse vibrations if the frequency is 200Hz. A. 6.21 B. 0.621 C. 62.1 D. 0.006

Last Answer : A. 6.21

Calculate the static deflection in μm of transverse vibrations if the frequency is 200Hz. a) 6 b) 0.6 c) 60 d) 0.006

Description : Calculate the static deflection in μm of transverse vibrations if the frequency is 200Hz. a) 6 b) 0.6 c) 60 d) 0.006

Last Answer : a) 6

The Minimum bar spacing should not be less than [ A ] Diameter of the largest bar [ B ] Maximum size of aggregate [ C ] Greater of diameter of the largest bar and maximum size of aggregate [ D ] Greater of diameter of the largest bar and maximum size of aggregate plus 5 mm

Description : The Minimum bar spacing should not be less than [ A ] Diameter of the largest bar [ B ] Maximum size of aggregate [ C ] Greater of diameter of the largest bar and maximum size of aggregate [ D ] Greater of diameter of the largest bar and maximum size of aggregate plus 5 mm

Last Answer : [ D ] Greater of diameter of the largest bar and maximum size of aggregate plus 5 mm

The length of each mitochondrion is about (A) 1.0 μm (B) 0.2 μm (C) 10 μm (D) 2.0 μm

Description : The length of each mitochondrion is about (A) 1.0 μm (B) 0.2 μm (C) 10 μm (D) 2.0 μm

Last Answer : (C) 10 μm

The minimum clear cover for R.C.C. columns shall be (A) Greater of 40 mm or diameter (B) Smaller of 40 mm or diameter (C) Greater of 25 mm or diameter (D) Smaller of 25 mm or diameter

Description : The minimum clear cover for R.C.C. columns shall be (A) Greater of 40 mm or diameter (B) Smaller of 40 mm or diameter (C) Greater of 25 mm or diameter (D) Smaller of 25 mm or diameter

Last Answer : Answer: Option C

Particulate' air pollutants are finely divided solids and liquids. Which of the following is not a ‘particulate’? (A) Dust & mists(B) Smoke & fumes(C) Photochemical smog & soot(D) None of these

Description : Particulate' air pollutants are finely divided solids and liquids. Which of the following is not a ‘particulate’? (A) Dust & mists (B) Smoke & fumes (C) Photochemical smog & soot (D) None of these

Last Answer : (D) None of these

A dash pot consists of a cylinder 10 cm in diameter in which slides a piston 12 cm long having a radial clearance of 1 mm. The cylinder is filled with oil having a viscosity of 1 poise. What will be the resistance offered by the piston to sliding with a velocity of 3 cm/sec a.1090 kg b.100 kg c.10900 kg d.10 kg e.50 kg

Description : A dash pot consists of a cylinder 10 cm in diameter in which slides a piston 12 cm long having a radial clearance of 1 mm. The cylinder is filled with oil having a viscosity of 1 poise. What will be the resistance offered ... with a velocity of 3 cm/sec a.1090 kg b.100 kg c.10900 kg d.10 kg e.50 kg

Last Answer : c. 10900 kg

A compression spring is made of music wire of 2 mm diameter having a shear strength and shear modulus of 800 Mpa and 80 Gpa respectively. The mean coil diameter is 20mm, free length is 40 mm, and the number of active coils is 10. If the mean coil diameter is reduced to 10 mm, the stiffness of the spring is approximately a. increased by 8 times b. decreased by 2 times c. increased by 2 times d. decreased by 8 times

Description : A compression spring is made of music wire of 2 mm diameter having a shear strength and shear modulus of 800 Mpa and 80 Gpa respectively. The mean coil diameter is 20mm, free length is 40 mm, and the number ... by 8 times b. decreased by 2 times c. increased by 2 times d. decreased by 8 times

Last Answer : a. increased by 8 times

My body gets darker in some places in winter . In summer, when you come in contact with powder or husk and dust and sand, you actually get redness on your face, sneezing, itching of nose, in winter, when you come in contact with them, you actually get redness on your face.

Description : My body gets darker in some places in winter . In summer, when you come in contact with powder or husk and dust and sand, you actually get redness on your face, sneezing, itching of nose, in winter, when you come in contact with them, you actually get redness on your face.

Last Answer : You have cold and skin allergies. Which is why these things are happening. Anyway, let's talk about cold allergies first. Don't let it get cold. Eat it mixed with hot water. Keep in mind that it ... skin wet. Apply Vaseline or olive oil. Give Dove Milk soap to your face every day. Drink more water.

The most efficient equipment for the removal of sub-micronic dust particles from blast furnace gas is the (A) Venturi atomiser (B) Gravity settling chamber (C) Electro-static precipitator (D) Cyclone separator

Description : The most efficient equipment for the removal of sub-micronic dust particles from blast furnace gas is the (A) Venturi atomiser (B) Gravity settling chamber (C) Electro-static precipitator (D) Cyclone separator

Last Answer : (C) Electro-static precipitator

Which is a secondary air pollutant? (A) Photochemical smog (B) Sulphur dioxide (C) Nitrogen dioxide (D) Dust particles

Description : Which is a secondary air pollutant? (A) Photochemical smog (B) Sulphur dioxide (C) Nitrogen dioxide (D) Dust particles

Last Answer : (A) Photochemical smog

Operating principle of cyclone separator is based on the action of __________ dust particles. (A) Diffusion of (B) Centrifugal force on (C) Gravitational force on (D) Electrostatic force on

Description : Operating principle of cyclone separator is based on the action of __________ dust particles. (A) Diffusion of (B) Centrifugal force on (C) Gravitational force on (D) Electrostatic force on

Last Answer : (B) Centrifugal force on

Which of the following dust collection equipments is the least efficient (for sub-micronic particles)? (A) Dust catcher (gravity type) (B) Cyclone separator (C) Bag filter (D) Hollow wet scrubber

Description : Which of the following dust collection equipments is the least efficient (for sub-micronic particles)? (A) Dust catcher (gravity type) (B) Cyclone separator (C) Bag filter (D) Hollow wet scrubber

Last Answer : (A) Dust catcher (gravity type)

Which is the most efficient dust removal equipment for removal of submicronic dust particles from blast furnace gas? (A) Packed scrubber (B) Gravity settling chamber (C) Electrostatic precipitator (D) Hydrocyclone

Description : Which is the most efficient dust removal equipment for removal of submicronic dust particles from blast furnace gas? (A) Packed scrubber (B) Gravity settling chamber (C) Electrostatic precipitator (D) Hydrocyclone

Last Answer : (C) Electrostatic precipitator

Which of the following is a secondary air pollutant? (A) Photochemical smog (B) Sulphur dioxide (C) Nitrogen dioxide (D) Dust particles

Description : Which of the following is a secondary air pollutant? (A) Photochemical smog (B) Sulphur dioxide (C) Nitrogen dioxide (D) Dust particles

Last Answer : (A) Photochemical smog

Pick out the wrong statement. (A) A slight haze at the top of chimney indicates good combustion in the furnace (B) A bag filter incurs very small pressure drop and is very efficient for removal of submicronic dust particles from flue gases at very high temperature (C) Electrostatic precipitator is the most efficient dust collection equipment for removal of submicronic dust particles present in flue gas (D) None of these

Description : Pick out the wrong statement. (A) A slight haze at the top of chimney indicates good combustion in the furnace (B) A bag filter incurs very small pressure drop and is very efficient for ... dust collection equipment for removal of submicronic dust particles present in flue gas (D) None of these

Last Answer : (B) A bag filter incurs very small pressure drop and is very efficient for removal of submicronic dust particles from flue gases at very high temperature

Raw Kerosene has a smoke point of 15 mm. After it is subjected to dearomatization by liquid SO2 extraction (Edeleanu process), its smoke point may become __________ mm. (A) 5 (B) 10 (C) 25 (D) 100

Description : Raw Kerosene has a smoke point of 15 mm. After it is subjected to dearomatization by liquid SO2 extraction (Edeleanu process), its smoke point may become __________ mm. (A) 5 (B) 10 (C) 25 (D) 100

Last Answer : (C) 25

Smoke volatility index is equal to smoke point plus (A) 0.42 × (% distilled at 204°C) (B) 5 mm (C) 0.84 × (% distilled at 204°C) (D) 10 mm approximately

Description : Smoke volatility index is equal to smoke point plus (A) 0.42 × (% distilled at 204°C) (B) 5 mm (C) 0.84 × (% distilled at 204°C) (D) 10 mm approximately

Last Answer : (A) 0.42 × (% distilled at 204°C)

Which of the following is the most suitable for cleaning of fine coal dust (<0.5 mm)? (A) Trough washer (B) Baum jig washer (C) Spiral separator (D) Froth floatation

Description : Which of the following is the most suitable for cleaning of fine coal dust (

Last Answer : (D) Froth floatation

Froth floatation is used for (A) Washing fine coal dust (< 0.5 mm size) (B) Washing lump coal (> 80 mm size) (C) Removing ash from the coal based on difference in specific gravity of coal and ash

Description : Froth floatation is used for (A) Washing fine coal dust (< 0.5 mm size) (B) Washing lump coal (> 80 mm size) (C) Removing ash from the coal based on difference in specific gravity of coal and ash

Last Answer : (A) Washing fine coal dust (< 0.5 mm size)

__________ substances present in sewage are removed in grit chamber during sewage treatment. (A) Organic (B) Fatty(C) Inorganic(D) Dissolved

Description : __________ substances present in sewage are removed in grit chamber during sewage treatment. (A) Organic (B) Fatty (C) Inorganic (D) Dissolved

Last Answer : (C) Inorganic

Fine grit present in sewage is removed in the __________ during sewage treatment. (A) Grit chamber (B) Detritus tank (C) Trickling filter (D) Skimming tank

Description : Fine grit present in sewage is removed in the __________ during sewage treatment. (A) Grit chamber (B) Detritus tank (C) Trickling filter (D) Skimming tank

Last Answer : (B) Detritus tank

If 20 kg of coarse aggregate is sieved through 80 mm, 40 mm, 20 mm, 10 mm, 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron standard sieves and the weights retained are 0 kg, 2 kg, 8 kg, 6 kg, 4 kg respectively, the fineness modulus of the aggregate, is (A) 7.30 (B) 7.35 (C) 7.40 (D) 7.45

Description : If 20 kg of coarse aggregate is sieved through 80 mm, 40 mm, 20 mm, 10 mm, 4.75 mm, 2.36 mm, 1.18 mm, 600 micron, 300 micron and 150 micron standard sieves and the weights retained are 0 kg, 2 kg, 8 kg, ... , the fineness modulus of the aggregate, is (A) 7.30 (B) 7.35 (C) 7.40 (D) 7.45

Last Answer : Answer: Option C

In screen analysis, the notation +5 mm/-10 mm means particles passing through (A) 10 mm screen and retained on 5 mm screen (B) 5 mm screen and retained on 10 mm screen (C) Both 5 mm and 10 mm screens (D) Neither 5 mm nor 10 mm screen

Description : In screen analysis, the notation +5 mm/-10 mm means particles passing through (A) 10 mm screen and retained on 5 mm screen (B) 5 mm screen and retained on 10 mm screen (C) Both 5 mm and 10 mm screens (D) Neither 5 mm nor 10 mm screen

Last Answer : (A) 10 mm screen and retained on 5 mm screen

The diameter of longitudinal bars of a column should never be less than (A) 6 mm (B) 8 mm (C) 10 mm (D) 12 mm

Description : The diameter of longitudinal bars of a column should never be less than (A) 6 mm (B) 8 mm (C) 10 mm (D) 12 mm

Last Answer : Answer: Option D

The diameter of main bars in R.C.C. columns, shall not be less than (A) 6 mm (B) 8 mm (C) 10 mm (D) 12 mm

Description : The diameter of main bars in R.C.C. columns, shall not be less than (A) 6 mm (B) 8 mm (C) 10 mm (D) 12 mm

Last Answer : Answer: Option D