A particle A of diameter 10 microns settles in an oil of specific gravity
0.9 and viscosity 10 poise under Stoke's law. A particle B with diameter 20microns settling in the same oil will have a settling velocity
(A) Same as that of A
(B) One fourth as that of A
(C) Twice as that of A
(D) Four times as that of A

1 Answer

Answer :

(B) One fourth as that of A

Related questions

Description : If the specific gravity of a soil particle of 0.05 cm diameter is 2.67, its terminal velocity while settling in distilled water of viscosity, 0.01 poise, is (A) 0.2200 cm/sec (B) 0.2225 cm/sec (C) 0.2250 cm/sec (D) 0.2275 cm/sec

Last Answer : (D) 0.2275 cm/sec

Description : The kinematic viscosity of an oil (in stokes) whose specific gravity is 0.95 and viscosity 0.011 poise, is (A) 0.0116 stoke (B) 0.116 stoke (C) 0.0611 stoke (D) 0.611 stoke

Last Answer : Answer: Option A

Description : Particle size range in which dust catcher (gravity settling chamber) works most effectively and efficiently is __________ microns. (A) < 5 (B) 10 to 25 (C) < 74 (D) > 1000

Last Answer : (C) < 74

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

Description : Brownian movement is prominent in the particle size range of __________ microns in case of settling of a particle in a fluid. (A) 2 to 3 (B) 0.01 to 0.10 (C) 200 to 300 (D) 100 to 1000

Last Answer : A) 2 to 3

Description : If G is the specific gravity of particles of diameter d, the velocity of settlement V in still water  at T°C, according to Stoke's law, is  (A) V = 418 (G - 1) d² [(3T + 70)/100]  (B) V = 418 (G - 1) d [(3T - ... 1) d² [(2T + 70)/100]  (D) V = 418 (G - 1) d 4  [(3T + 70)/100] 

Last Answer : (A) V = 418 (G - 1) d² [(3T + 70)/100] 

Description : The terminal velocity of a solid spherical particle falling through a stationary fluid mass in the Stoke's law range is proportional to the (A) Inverse of fluid viscosity (B) Square of particle size (C) Difference in the densities of the particle & fluid (D) All (A), (B) and (C)

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

Description : Stoke's law states that the velocity at which a grain settles out of suspension, the other factors remaining constant, is dependent upon (A) Shape of grain (B) Weight of grain (C) Size of grain (D) Shape, size and weight of grain

Last Answer : Answer: Option D

Description : The terminal velocity of a small sphere settling in a viscous fluid varies as the (A) First power of its diameter (B) Inverse of the fluid viscosity (C) Inverse square of the diameter (D) Square of the difference in specific weights of solid & fluid

Last Answer : (B) Inverse of the fluid viscosity

Description : The settling velocity of a spherical particle of diameter less than 0.1 mm as per Stock’s law, is A. Vs = 418 (Gs – Gw) d [(3T + 70)/100] B. Vs = 418 (Gs – Gw)d² [(3T + 70)/100] C. Vs = 218 (Gs – Gw)d² [(3T + 70)/100] D. Vs = 218 (Gs – Gw)d [(3T + 70)/100]

Last Answer : ANS: B

Description : A particle is settling in a liquid under Stokesian conditions. The free falling velocity of the particle is proportional to (A) √(Particle diameter) (B) Particle diameter (C) (Particle diameter)2 (D) (Particle diameter)3

Last Answer : B) Particle diameter

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

Description : The terminal velocity of a particle moving through a fluid varies as dp n . The value of n is equal to __________ in Stoke's law regime. (A) 1 (B) 0.5 (C) 2 (D) 1.5

Last Answer : (C) 2

Description : A suspended particle falls through a height minutes. If the viscosity of water is and specific gravity of the particle is , the diameter of the particle is (where M is a constant factor) (A) 103M (H/t) (B) 104M (H/t) (C) 105M (H/t) (D) 102M (H/t)

Last Answer : Answer: Option C

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

Description : Reynolds number for water flow through a tube of I.D. 5 cm is 1500. If a liquid of 5 centipoise viscosity and 0.8 specific gravity flows in the same pipe at the same velocity, then the pressure drop will (A) Increase (B) Decrease (C) Remain same (D) Data insufficient to predict pressure drop

Last Answer : (A) Increase

Description : Poise is converted into stoke by (A) Multiplying with density (gm/c.c) (B) Dividing by density (gm/c.c) (C) Multiplying with specific gravity (D) Dividing by specific gravity

Last Answer : (B) Dividing by density (gm/c.c)

Description : The kinematic viscosity (in stoke) and the absolute/dynamic viscosity (in poise) are the same for __________ at room temperature. (A) Air (B) Water (C) Mercury (D) Alcohol

Last Answer : (B) Water

Description : Two particles are called to be equal settling, if they are having the same. (A) Size (B) Specific gravity (C) Terminal velocities in the same fluid & in the same field of force (D) None of these

Last Answer : (C) Terminal velocities in the same fluid & in the same field of force

Description : Capillary tube method of viscosity measurement is based on the (A) Hagen-Poiseuille’s equation (B) Stoke's law (C) Navier-stokes equation (D) None of these

Last Answer : (A) Hagen-Poiseuille’s equation

Description : Minimum fluidisation velocity for a specific system depends upon the (A) Particle size (B) Fluid viscosity (C) Density of both the particle & the fluid (D) All (A), (B) and (C)

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

Description : For a particle settling in water at its terminal settling velocity, which of the following is true? (A) Buoyancy = weight + drag (B) Weight = buoyancy + drag (C) Drag = buoyancy + weight (D) Drag = weight

Last Answer : (B) Weight = buoyancy + drag

Description : Stoke's law does not hold good if the size of particle is smaller than (A) 0.0002 mm (B) 0.002 mm (C) 0.02 mm (D) 0.2 mm

Last Answer : (A) 0.0002 mm

Description : Stoke's law is valid only if the size of particle is (A) Less than 0.0002 mm (B) Greater than 0.2 mm (C) Between 0.2 mm and 0.0002 mm (D) All of the above

Last Answer : Answer: Option C

Description : Stoke's law is valid, when the particle Reynolds number is (A) < 1 (B) > 1 (C) < 5 (D) None of these

Last Answer : (A) < 1

Description : In the Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass is __________ the fluid viscosity. (A) Directly proportional to (B) Inversely proportional to (C) Inversely proportional to the square root of (D) Independent of

Last Answer : (B) Inversely proportional to

Description : N. second/m2 is (A) The S.I. unit of dynamic viscosity (B) The S.I. unit of kinematic viscosity (C) Equivalent to one poise (D) Equivalent to one stoke

Last Answer : (A) The S.I. unit of dynamic viscosity

Description : One poise (unit of absolute/dynamic viscosity) is equivalent to one (A) gm/cm2 . sec (B) gm/cm. sec (C) cm2 /sec (D) m2 /sec

Last Answer : (B) gm/cm. sec

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

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

Description : In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is A. Q/(B × D) B. Q/(L × D) C. Q/L D. Q/(B × L)

Last Answer : ANS: D

Description : Compare water and oil of specific gravity 0.8 on the basis of density & viscosity.

Last Answer : Here it is not possible to find out viscosity

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

Description : Pick out the additive property of lube oil out of following. (A) °API gravity (B) Specific gravity (C) Viscosity (D) Flashpoint

Last Answer : (A) °API gravity

Description : The liquid used for the washing of coal in an industrial coal washery is a mixture of water and (A) Carbon tetrachloride (B) Sand (40%) (C) Mineral oil of high viscosity & specific gravity (1.6) (D) None of these

Last Answer : (B) Sand (40%)

Description : For the Stoke's law to be valid in the case of a falling sphere in a fluid, the (A) Reynolds number (based on sphere diameter) should be < 1 (B) Flow around the sphere should be in turbulent region (C) Sphere must be metallic (D) Fluid density should be constant

Last Answer : (C) Sphere must be metallic

Description : Pick out the wrong statement. (A) A fluid mass is free from shearing forces, when it is made to rotate with a uniform velocit (B) Newton's law of viscosity is not applicable to the ... types of bearings (D) Rise of water in capillary tubes reduces with the increasing diameter of capillary tubes

Last Answer : (B) Newton's law of viscosity is not applicable to the turbulent flow of fluid with linear velocity distribution

Description : Poise is the unit of (A) Surface tension (B) Capillarity (C) Viscosity (D) Shear stress in fluids

Last Answer : Answer: Option C

Description : Which of the following is the unit of kinematic viscosity? (A) Pascal (B) Poise (C) Stoke (D) Faraday

Last Answer : Answer: Option C

Description : The unit of dynamic viscosity in S.I. units is (A) N-m/s2 (B) N-s/m2 (C) Poise (D) Stoke

Last Answer : Answer: Option B

Description : The viscosity of water at 20°C is (A) One stoke (B) One centistoke (C) One poise (D) One centipoise

Last Answer : Answer: Option D

Description : A Poise is the unit of measure of which of the following? w) pressure x) viscosity y) force z) mass

Last Answer : ANSWER: X -- VISCOSITY

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

Description : In Newton's law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the __________ of its diameter. (A) Inverse (B) Square root (C) Second power (D) First power

Last Answer : (B) Square root

Description : Pick out the wrong statement. (A) Hammer crushers operate by impact action (B) Standard screens have circular opening (C) With increase in mesh number of screens, their diameter in microns decreases (D) 200 mesh screen has 200 openings per linear cm

Last Answer : (D) 200 mesh screen has 200 openings per linear cm

Description : For the free settling of a spherical particle through a fluid, the slope of, CD-log NRe , plot is (A) 1 (B) -1 (C) 0.5 (D) -0.5

Last Answer : (B) -1

Description : A 300 mm square bearing plate settles by 15 mm in a plate load test on a cohesive soil when the intensity of loading is 0.2 N/mm². The settlement of a prototype shallow footing 1 m square under the same intensity of loading is (A) 15 mm (B) 30 mm (C) 50 mm (D) 167 mm

Last Answer : (C) 50 mm

Description : A 600 mm square bearing plate settles by 15 mm in plate load test on a cohesion-less soil under an intensity of loading of 0.2 N/ram². The settlement of a prototype shallow footing 1 m square under the same intensity of ... (A) 15 mm (B) Between 15 mm and 25 mm (C) 25 mm (D) Greater than 25 mm

Last Answer : Answer: Option B

Description : Pick out the wrong statement pertaining to fluid flow. (A) The ratio of average velocity to the maximum velocity for turbulent flow of Newtonian fluid in circular pipes is 0.5 (B) The Newtonian ... at the centre of the pipe (C) Navier-Stokes equation is applicable to the analysis of viscous flows

Last Answer : (A) The ratio of average velocity to the maximum velocity for turbulent flow of Newtonian fluid in circular pipes is 0.5

Description : If the distance between the earth and the sun were twice what it is now, the gravitational force exerted on the earth by the sun would be (a) twice as large as it is now (b) four times as large as it is now (c) half of what it is now (d) one-fourth of what it is now

Last Answer : Ans:(d)